MD Settings: convert paper-icon-button to paper-icon-button-light.

chrome/browser/resources/settings/people_page/camera.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 
 <link rel="import" href="chrome://resources/html/util.html">
-<link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
+<link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button-light.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-spinner/paper-spinner.html">
 <link rel="import" href="../icons.html">
 <link rel="import" href="../settings_shared_css.html">
 
 <dom-module id="settings-camera">
   <template>
     <style include="settings-shared">
       #perspectiveBox {
         height: 228px;
         perspective: 600px;
@@ skipping 28 matching lines @@
       }
 
       #cameraControls {
         background-color: var(--paper-grey-800);
         border-bottom-left-radius: 2px;
         border-bottom-right-radius: 2px;
         padding: 8px;
       }
 
       #flipPhoto {
-        --iron-icon-fill-color: white;
         float: right;
       }
 
       :host-context([dir=rtl]) #flipPhoto {
         float: left;
       }
 
       #takePhoto {
-        --iron-icon-fill-color: white;
         background-color: var(--paper-green-500);
         border-radius: 50%;
         display: block;
         margin: 0 auto 0 auto;
       }
     </style>
     <div hidden="[[!cameraActive]]">
       <div id="perspectiveBox">
         <div id="userImageStreamCrop">
           <video id="cameraVideo" autoplay hidden="[[!cameraOnline_]]"></video>
           <paper-spinner active="[[!cameraOnline_]]"></paper-spinner>
         </div>
       </div>
       <div id="cameraControls">
-        <paper-icon-button id="flipPhoto" tabindex="2"
-            icon="settings:flip" title="$i18n{flipPhoto}"
-            on-tap="onTapFlipPhoto_" disabled="[[!cameraOnline_]]">
-        </paper-icon-button>
-        <paper-icon-button id="takePhoto" tabindex="1"
-            icon="settings:camera-alt" title="$i18n{takePhoto}"
-            on-tap="takePhoto" disabled="[[!cameraOnline_]]">
-        </paper-icon-button>
+        <button is="paper-icon-button-light" id="flipPhoto" tabindex="2"
+            title="$i18n{flipPhoto}" on-tap="onTapFlipPhoto_"
+            disabled="[[!cameraOnline_]]" class="icon-flip">
+        </button>
+        <button is="paper-icon-button-light" id="takePhoto" tabindex="1"
+            title="$i18n{takePhoto}" on-tap="takePhoto"
+            disabled="[[!cameraOnline_]]" class="icon-camera-alt">
+        </button>
       </div>
     </div>
   </template>
   <script src="camera.js"></script>
 </dom-module>