https://github.com/Polymer/polymer-dev/blob/b25604a5f7d765e51e8984dcc2b9c5680695b565/src/instance/properties.js#L129
function bindProperties(inA, inProperty, observable) {
log.bind && console.log(LOG_BIND_PROPS, inB.localName || 'object', inPath, inA.localName, inProperty);
"inB" and "inPath" ... looks like leftover code from the old impl
https://github.com/Polymer/polymer-dev/blob/b25604a5f7d765e51e8984dcc2b9c5680695b565/src/instance/properties.js#L129
"inB" and "inPath" ... looks like leftover code from the old impl