New Features

• Property observers can now take a function reference in addition to taking a string name
  • Example

    class XFoo extends Polymer.Element {
      static get properties() {
        return {
          prop: {
            type: String,
            observer: function (newProp, oldProp) {
              return this.prop2Changed(newProp, oldProp);
            }
          }
        };
      }
    }

Meaningful Changes

• When using Polymer.passiveTouchGestures, don't set passive on touchend events, allowing tap and up gestures to prevent click.
• Do not collapse multiple styles into a single style, which allows for lower memory usage in native ShadowDOM. ShadyCSS and ShadyDOM polyfill will still collapse into one style for now.
• dom-repeat will now always resort and/or refilter an array when an item changes.

Raw Notes

• [ci skip] commit new version in lib/utils/boot.html when using npm version (commit)

• change PolymerElement extern to var (commit)

• update node devDependencies (commit)

• fix lint error (commit)

• Fix :dir selectors with nested custom elements (commit)

• Update test to be more descriptive (commit)

• Annotate Polymer function with @global. (#4967) (commit)

• make PASSIVE_TOUCH take an argument (commit)

• Do not set touchend listeners to passive (commit)

• Add some @function annotations to APIs that are defined by assignment. (commit)

• add return jsdoc to void functions (commit)

• Update CONTRIBUTING.md (commit)

• Fix typo. (commit)

• Comment reworded based on feedback. (commit)

• Semantic issue (proposal) plus minor fixes (commit)

• Depend on webcomponents and shadycss with shady-unscoped support (commit)

• Also clarify delay units. Fixes #4707 (commit)

• Ensure re-sort/filter always happens after array item set. Fixes #3626 (commit)

• Clarify docs on target-framerate. Fixes #4897 (commit)

• move test after (commit)

• test more permutations (commit)

• Fix missing comma in Path.translate JSDoc (commit)

• fix(bower): standardized version tagging (#4921) (commit)

• Minor fixes (update URLs) (commit)

• add license headers (commit)

• Prep for processing of shady-unscoped moving to ShadyCSS (commit)

• Implement type change in Polymer.ElementMixin (commit)

• instance.$.foo should only give Elements (commit)

• Annotate DomApi with @memberof Polymer (commit)

• Clarify all elements between changes must apply mixing. Fixes #4914 (commit)

• add safari 11 to sauce testing (commit)

• Fix tests on Firefox. (commit)

• Update externs again. (commit)

• Update externs. (commit)

• Lint fixes (commit)

• Allow style elements to be separate in the element template. (commit)

• Lint fix. (commit)

• Add support for styles with a shady-unscoped attribute (commit)

• [ci skip] Update CHANGELOG (commit)

• [ci skip] version script did not work as expected (commit)

• adding test case for 4696 4706 (commit)

• Support property observers which are direct function references in addition to strings. Provides better static analysis and refactoring support in multiple tools. Alleviates the need for property reflection with Closure-compiler renaming. (commit)

• removing package-lock.json from PR (commit)

• implementing the code review suggestions (commit)

• Updating deserialize function (use of ternary operation). Fixes #4696 (commit)

• Updating deserialize function. Fixes #4696 (commit)