Remove third_party/polymer from .gitignore

third_party/polymer/v1_0/components/paper-icon-button/paper-icon-button.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
-The complete set of authors may be found at http://polymer.github.io/AUTHORS
-The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS
-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
--->
-
-<link rel="import" href="../polymer/polymer.html">
-<link rel="import" href="../iron-icon/iron-icon.html">
-<link rel="import" href="../iron-flex-layout/iron-flex-layout.html">
-<link rel="import" href="../paper-styles/default-theme.html">
-<link rel="import" href="../paper-behaviors/paper-button-behavior.html">
-<link rel="import" href="../paper-behaviors/paper-inky-focus-behavior.html">
-<link rel="import" href="../paper-ripple/paper-ripple.html">
-
-<!--
-Material Design: <a href="http://www.google.com/design/spec/components/buttons.html">Buttons</a>
-
-`paper-icon-button` is a button with an image placed at the center. When the user touches
-the button, a ripple effect emanates from the center of the button.
-
-`paper-icon-button` includes a default icon set.  Use `icon` to specify which icon
-from the icon set to use.
-
-    <paper-icon-button icon="menu"></paper-icon-button>
-
-See [`iron-iconset`](#iron-iconset) for more information about
-how to use a custom icon set.
-
-Example:
-
-    <link href="path/to/iron-icons/iron-icons.html" rel="import">
-
-    <paper-icon-button icon="favorite"></paper-icon-button>
-    <paper-icon-button src="star.png"></paper-icon-button>
-
-###Styling
-
-Style the button with CSS as you would a normal DOM element. If you are using the icons
-provided by `iron-icons`, they will inherit the foreground color of the button.
-
-    /* make a red "favorite" button */
-    <paper-icon-button icon="favorite" style="color: red;"></paper-icon-button>
-
-By default, the ripple is the same color as the foreground at 25% opacity. You may
-customize the color using this selector:
-
-    /* make #my-button use a blue ripple instead of foreground color */
-    #my-button::shadow #ripple {
-      color: blue;
-    }
-
-The opacity of the ripple is not customizable via CSS.
-
-The following custom properties and mixins are available for styling:
-
-Custom property | Description | Default
-----------------|-------------|----------
-`--paper-icon-button-disabled-text` | The color of the disabled button | `--primary-text-color`
-`--paper-icon-button-ink-color` | Selected/focus ripple color | `--default-primary-color`
-`--paper-icon-button` | Mixin for a button | `{}`
-`--paper-icon-button-disabled` | Mixin for a disabled button | `{}`
-
-@group Paper Elements
-@element paper-icon-button
-@demo demo/index.html
--->
-
-<dom-module id="paper-icon-button">
-  <style>
-
-    :host {
-      display: inline-block;
-      position: relative;
-      padding: 8px;
-      outline: none;
-      -webkit-tap-highlight-color: rgba(0,0,0,0);
-      -webkit-user-select: none;
-      -moz-user-select: none;
-      -ms-user-select: none;
-      user-select: none;
-      cursor: pointer;
-      z-index: 0;
-
-      @apply(--paper-icon-button);
-    }
-
-    :host #ink {
-      color: var(--paper-icon-button-ink-color, --primary-text-color);
-      opacity: 0.6;
-    }
-
-    :host([disabled]) {
-      color: var(--paper-icon-button-disabled-text, --disabled-text-color);
-      pointer-events: none;
-      cursor: auto;
-      @apply(--paper-icon-button-disabled);
-    }
-  </style>
-  <template>
-    <paper-ripple id="ink" class="circle" center></paper-ripple>
-    <iron-icon id="icon" src="[[src]]" icon="[[icon]]" alt$="[[alt]]"></iron-icon>
-  </template>
-</dom-module>
-<script>
-  Polymer({
-    is: 'paper-icon-button',
-
-    hostAttributes: {
-      role: 'button',
-      tabindex: '0'
-    },
-
-    behaviors: [
-      Polymer.PaperInkyFocusBehavior
-    ],
-
-    properties: {
-      /**
-       * The URL of an image for the icon. If the src property is specified,
-       * the icon property should not be.
-       */
-      src: {
-        type: String
-      },
-
-      /**
-       * Specifies the icon name or index in the set of icons available in
-       * the icon's icon set. If the icon property is specified,
-       * the src property should not be.
-       */
-      icon: {
-        type: String
-      },
-
-      /**
-       * Specifies the alternate text for the button, for accessibility.
-       */
-      alt: {
-        type: String,
-        observer: "_altChanged"
-      }
-    },
-
-    _altChanged: function(newValue, oldValue) {
-      var label = this.getAttribute('aria-label');
-
-      // Don't stomp over a user-set aria-label.
-      if (!label || oldValue == label) {
-        this.setAttribute('aria-label', newValue);
-      }
-    }
-  });
-</script>