[MD WebUI] Move icons used in Bookmarks and Settings to shared file.

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

 <link rel="import" href="chrome://resources/cr_elements/cr_dialog/cr_dialog.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_expand_button/cr_expand_button.html">
 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/icon.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-collapse/iron-collapse.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
@@ skipping 36 matching lines @@
         border-radius: 20px;
         flex-shrink: 0;
         height: 40px;
         width: 40px;
       }
 
       #managed-by-domain-name {
         font-weight: bold;
       }
 
-      iron-icon[icon='settings:sync'] {
+      iron-icon[icon='cr:sync'] {
        --iron-icon-fill-color: var(--google-green-700);
       }
 
-      #sync-status[actionable] iron-icon[icon='settings:sync-problem'] {
+      #sync-status[actionable] iron-icon[icon='cr:sync-problem'] {
        --iron-icon-fill-color: var(--settings-error-color);
       }
 
       #sync-status:not([actionable]) .subpage-arrow {
         display: none;
       }
 
       .settings-box[actionable] .sync-error {
         color: var(--settings-error-color);
       }
@@ skipping 314 matching lines @@
 <if expr="chromeos">
     <template is="dom-if" if="[[showEasyUnlockTurnOffDialog_]]">
       <easy-unlock-turn-off-dialog id="easyUnlockTurnOffDialog"
           on-close="onEasyUnlockTurnOffDialogClose_">
       </easy-unlock-turn-off-dialog>
     </template>
 </if>
   </template>
   <script src="people_page.js"></script>
 </dom-module>