First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

… Gecko's.

Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed:
1. now it reports parsing errors on empty string
2. normalize_angle is changed to align with Gecko

MozReview-Commit-ID: my5P5khDb3

…=emilio

Stylo - support image-orientation property

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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<!-- Reviewable:end -->

…=bholley

Stylo - support image-orientation property

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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<!-- Reviewable:end -->

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

…=bholley

Stylo - support image-orientation property

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

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<!-- Reviewable:end -->

…=bholley

Stylo - support image-orientation property

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

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<!-- Reviewable:end -->

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 6dd690aa705c3e6f145e2109ac0d2a0cb0effd23

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

A recent spec change means that 0 is no longer supported as a valid
value for angles.
w3c/csswg-drafts#1162 (comment)

We add use counters to detect how often 0 is currently being used as
an angle.

image-orientation and rotate and offset-path's ray() have not yet
shipped, so we don't need use counters for these, we simply reject 0
as an angle.

ConsumeGradientAngleOrPercent now accepts a CSSParserContext by
const reference.

ConsumeGradientLengthOrPercent has been implemented with the same
function signature as ConsumeGradientAngleOrPercent so they can
be called via ConsumeGradientColorStops using the same function pointer type.

BUG=725382

Review-Url: https://codereview.chromium.org/2898133002
Cr-Commit-Position: refs/heads/master@{#474578}

We introduce web platform tests for parsing of
- offset-position
- offset-path
- offset-distance
- offset-rotate
- offset-anchor

The unshipped properties offset-position and offset-anchor currently
fail a test because we have not yet updated position parsing for
a recent CSS Values spec change (see http://crbug.com/717833).

offset-rotate currently fails a test because we parse 0 as an angle.
This was correct (but leads to shorthand parsing ambiguities) until
w3c/csswg-drafts#1162

offset-path fails some tests because we don't yet support url or
basic-shape || geometry-box shapes.

BUG=722757

Review-Url: https://codereview.chromium.org/2886703002
Cr-Commit-Position: refs/heads/master@{#474881}

We introduce web platform tests for parsing of
- offset-position
- offset-path
- offset-distance
- offset-rotate
- offset-anchor

The unshipped properties offset-position and offset-anchor currently
fail a test because we have not yet updated position parsing for
a recent CSS Values spec change (see http://crbug.com/717833).

offset-rotate currently fails a test because we parse 0 as an angle.
This was correct (but leads to shorthand parsing ambiguities) until
w3c/csswg-drafts#1162

offset-path fails some tests because we don't yet support url or
basic-shape || geometry-box shapes.

BUG=722757

Review-Url: https://codereview.chromium.org/2886703002
Cr-Commit-Position: refs/heads/master@{#474881}

We introduce web platform tests for parsing of
- offset-position
- offset-path
- offset-distance
- offset-rotate
- offset-anchor

The unshipped properties offset-position and offset-anchor currently
fail a test because we have not yet updated position parsing for
a recent CSS Values spec change (see http://crbug.com/717833).

offset-rotate currently fails a test because we parse 0 as an angle.
This was correct (but leads to shorthand parsing ambiguities) until
w3c/csswg-drafts#1162

offset-path fails some tests because we don't yet support url or
basic-shape || geometry-box shapes.

BUG=722757

Review-Url: https://codereview.chromium.org/2886703002
Cr-Commit-Position: refs/heads/master@{#474881}

A recent spec change means that 0 is no longer supported as a valid value for angles.
w3c/csswg-drafts#1162 (comment)

Linear gradients, like CSS transform, are an exception and are explicitly specified
to support unitless 0, to avoid breaking existing pages:
https://drafts.csswg.org/css-images-3/#linear-gradients
https://drafts.csswg.org/css-transforms/#valdef-transform-rotate

Conic gradients, being a new feature that has not yet shipped in browsers, should
only support angles with explicit units.
https://drafts.csswg.org/css-images-4/#conic-gradients

We update the parsing of conic gradients to reject unitless 0 angles.

BUG=727195

Review-Url: https://codereview.chromium.org/2908053002
Cr-Commit-Position: refs/heads/master@{#475562}

A recent spec change means that 0 is no longer supported as a valid value for angles.
w3c/csswg-drafts#1162 (comment)

As registerProperty has not yet shipped, we can reject unitless 0
angles without breaking legacy pages.

BUG=727195

Review-Url: https://codereview.chromium.org/2917573002
Cr-Commit-Position: refs/heads/master@{#475858}

Angles in offset-rotate must specify units.
w3c/csswg-drafts#1162 (comment)

Discussed in Intent:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/mP-bj7jCyvM/UChplbzpBgAJ

Bug: 727195
Change-Id: Iac2e641b3a35c92bdf26e441d52d520469ef3ee6
Reviewed-on: https://chromium-review.googlesource.com/522483
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Rune Lillesveen <rune@opera.com>
Commit-Queue: Eric Willigers <ericwilligers@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477398}

Angles in offset-rotate must specify units.
w3c/csswg-drafts#1162 (comment)

Discussed in Intent:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/mP-bj7jCyvM/UChplbzpBgAJ

Bug: 727195
Change-Id: Iac2e641b3a35c92bdf26e441d52d520469ef3ee6
Reviewed-on: https://chromium-review.googlesource.com/522483
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Rune Lillesveen <rune@opera.com>
Commit-Queue: Eric Willigers <ericwilligers@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477398}

Angles in offset-rotate must specify units.
w3c/csswg-drafts#1162 (comment)

Discussed in Intent:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/mP-bj7jCyvM/UChplbzpBgAJ

Bug: 727195
Change-Id: Iac2e641b3a35c92bdf26e441d52d520469ef3ee6
Reviewed-on: https://chromium-review.googlesource.com/522483
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Rune Lillesveen <rune@opera.com>
Commit-Queue: Eric Willigers <ericwilligers@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477398}

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

UltraBlame original commit: 8679fa3e5db49772f81ab6cfad2652e50ff79d92

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

UltraBlame original commit: 8679fa3e5db49772f81ab6cfad2652e50ff79d92

…m chenpighead:stylo-image-orientation-support); r=bholley

First, we need to make Servo's image-orientation parser to be agreed with Gecko's.
Numbers without any AngleUnit, including unitless 0 angle, should be invalid
for image-orientation. However, rotate() and skew() for transform properties
accept unitless 0 angle. In order to make all these properties work properly,
I fixed Angle::parse() to match Gecko. For the existing users of Angle::parse(),
I create Angle::parse_with_unitless() and use it as an alternative for them.
Once w3c/csswg-drafts#1162 is resolved, we shall be
able to use an unified version of Angle::parse() then.

The parser of image-orientation is also fixed to report parsing errors on
empty string.

Then, with the newly added binding functions support in Gecko side, we shall
reuse the same methods from Gecko to pass the computed value from Servo to Gecko.

Gecko bug: Bug 1341758

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Source-Repo: https://github.com/servo/servo
Source-Revision: 2544c085214f368ec0a189bd8aefd7d83f75563b

UltraBlame original commit: 8679fa3e5db49772f81ab6cfad2652e50ff79d92