Remove third_party/polymer from .gitignore

third_party/polymer/v1_0/components/iron-resizable-behavior/iron-resizable-behavior.html

-<!--
-@license
-Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
-This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
-The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
-The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
-Code distributed by Google as part of the polymer project is also
-subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
--->
-
-<link rel="import" href="../polymer/polymer.html">
-
-<script>
-  /**
-   * `IronResizableBehavior` is a behavior that can be used in Polymer elements to
-   * coordinate the flow of resize events between "resizers" (elements that control the
-   * size or hidden state of their children) and "resizables" (elements that need to be
-   * notified when they are resized or un-hidden by their parents in order to take
-   * action on their new measurements).
-   * Elements that perform measurement should add the `IronResizableBehavior` behavior to
-   * their element definition and listen for the `iron-resize` event on themselves.
-   * This event will be fired when they become showing after having been hidden,
-   * when they are resized explicitly by another resizable, or when the window has been
-   * resized.
-   * Note, the `iron-resize` event is non-bubbling.
-   *
-   * @polymerBehavior Polymer.IronResizableBehavior
-   * @demo demo/index.html
-   **/
-  Polymer.IronResizableBehavior = {
-    properties: {
-      /**
-       * The closest ancestor element that implements `IronResizableBehavior`.
-       */
-      _parentResizable: {
-        type: Object,
-        observer: '_parentResizableChanged'
-      },
-
-      /**
-       * True if this element is currently notifying its descedant elements of
-       * resize.
-       */
-      _notifyingDescendant: {
-        type: Boolean,
-        value: false
-      }
-    },
-
-    listeners: {
-      'iron-request-resize-notifications': '_onIronRequestResizeNotifications'
-    },
-
-    created: function() {
-      // We don't really need property effects on these, and also we want them
-      // to be created before the `_parentResizable` observer fires:
-      this._interestedResizables = [];
-      this._boundNotifyResize = this.notifyResize.bind(this);
-    },
-
-    attached: function() {
-      this.fire('iron-request-resize-notifications', null, {
-        node: this,
-        bubbles: true,
-        cancelable: true
-      });
-
-      if (!this._parentResizable) {
-        window.addEventListener('resize', this._boundNotifyResize);
-        this.notifyResize();
-      }
-    },
-
-    detached: function() {
-      if (this._parentResizable) {
-        this._parentResizable.stopResizeNotificationsFor(this);
-      } else {
-        window.removeEventListener('resize', this._boundNotifyResize);
-      }
-
-      this._parentResizable = null;
-    },
-
-    /**
-     * Can be called to manually notify a resizable and its descendant
-     * resizables of a resize change.
-     */
-    notifyResize: function() {
-      if (!this.isAttached) {
-        return;
-      }
-
-      this._interestedResizables.forEach(function(resizable) {
-        if (this.resizerShouldNotify(resizable)) {
-          this._notifyDescendant(resizable);
-        }
-      }, this);
-
-      this._fireResize();
-    },
-
-    /**
-     * Used to assign the closest resizable ancestor to this resizable
-     * if the ancestor detects a request for notifications.
-     */
-    assignParentResizable: function(parentResizable) {
-      this._parentResizable = parentResizable;
-    },
-
-    /**
-     * Used to remove a resizable descendant from the list of descendants
-     * that should be notified of a resize change.
-     */
-    stopResizeNotificationsFor: function(target) {
-      var index = this._interestedResizables.indexOf(target);
-
-      if (index > -1) {
-        this._interestedResizables.splice(index, 1);
-        this.unlisten(target, 'iron-resize', '_onDescendantIronResize');
-      }
-    },
-
-    /**
-     * This method can be overridden to filter nested elements that should or
-     * should not be notified by the current element. Return true if an element
-     * should be notified, or false if it should not be notified.
-     *
-     * @param {HTMLElement} element A candidate descendant element that
-     * implements `IronResizableBehavior`.
-     * @return {boolean} True if the `element` should be notified of resize.
-     */
-    resizerShouldNotify: function(element) { return true; },
-
-    _onDescendantIronResize: function(event) {
-      if (this._notifyingDescendant) {
-        event.stopPropagation();
-        return;
-      }
-
-      // NOTE(cdata): In ShadowDOM, event retargetting makes echoing of the
-      // otherwise non-bubbling event "just work." We do it manually here for
-      // the case where Polymer is not using shadow roots for whatever reason:
-      if (!Polymer.Settings.useShadow) {
-        this._fireResize();
-      }
-    },
-
-    _fireResize: function() {
-      this.fire('iron-resize', null, {
-        node: this,
-        bubbles: false
-      });
-    },
-
-    _onIronRequestResizeNotifications: function(event) {
-      var target = event.path ? event.path[0] : event.target;
-
-      if (target === this) {
-        return;
-      }
-
-      if (this._interestedResizables.indexOf(target) === -1) {
-        this._interestedResizables.push(target);
-        this.listen(target, 'iron-resize', '_onDescendantIronResize');
-      }
-
-      target.assignParentResizable(this);
-      this._notifyDescendant(target);
-
-      event.stopPropagation();
-    },
-
-    _parentResizableChanged: function(parentResizable) {
-      if (parentResizable) {
-        window.removeEventListener('resize', this._boundNotifyResize);
-      }
-    },
-
-    _notifyDescendant: function(descendant) {
-      // NOTE(cdata): In IE10, attached is fired on children first, so it's
-      // important not to notify them if the parent is not attached yet (or
-      // else they will get redundantly notified when the parent attaches).
-      if (!this.isAttached) {
-        return;
-      }
-
-      this._notifyingDescendant = true;
-      descendant.notifyResize();
-      this._notifyingDescendant = false;
-    }
-  };
-</script>
-