[MD settings] help button in content settings site lists

chrome/browser/resources/settings/privacy_page/privacy_page.html

 <link rel="import" href="chrome://resources/cr_elements/policy/cr_policy_vars_css.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-flex-layout/iron-flex-layout-classes.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-icon-button/paper-icon-button-light.html">
 <link rel="import" href="/clear_browsing_data_dialog/clear_browsing_data_dialog.html">
 <link rel="import" href="/controls/settings_checkbox.html">
 <link rel="import" href="/route.html">
 <link rel="import" href="/settings_page/settings_animated_pages.html">
@@ skipping 168 matching lines @@
       </template>
 
       <template is="dom-if" route-path="/siteSettings/all" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryAllSites}">
           <all-sites selected-site="{{selectedSite}}"></all-sites>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/automaticDownloads"
           no-search>
         <settings-subpage page-title="$i18n{siteSettingsAutomaticDownloads}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>

[dschuyler, 2016/10/20 23:27:46]

dpapad@ and I discussed a few ways this button could be added.
None of the options seemed amazing, so I chose one. This has 
the downside of repeating several times in this file, but imo
the other options were slightly less good.

           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.AUTOMATIC_DOWNLOADS}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/backgroundSync" no-search>
           no-search>
         <settings-subpage page-title="$i18n{siteSettingsBackgroundSync}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.BACKGROUND_SYNC}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/camera" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryCamera}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.CAMERA}}">
             <media-picker type="camera" class="media-picker"></media-picker>
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/cookies" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryCookies}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.COOKIES}}">
             <div class="settings-box cookie-controls">
               <settings-checkbox class="start"
                   label="$i18n{thirdPartyCookie}"
                   sub-label="$i18n{thirdPartyCookieSublabel}"
                   pref="{{prefs.profile.block_third_party_cookies}}">
               </settings-checkbox>
             </div>
             <site-data class="site-data"></site-data>
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/images" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryImages}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.IMAGES}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/location" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryLocation}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.GEOLOCATION}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/handlers" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryHandlers}">
           <protocol-handlers></protocol-handlers>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/zoomLevels" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryZoomLevels}">
           <zoom-levels></zoom-levels>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/javascript" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryJavascript}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.JAVASCRIPT}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/keygen" no-search>
         <settings-subpage page-title="$i18n{siteSettingsKeygen}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.KEYGEN}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/microphone" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryMicrophone}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.MIC}}">
             <media-picker type="mic" class="media-picker"></media-picker>
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/notifications" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryNotifications}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.NOTIFICATIONS}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/flash" no-search>
         <settings-subpage page-title="$i18n{siteSettingsFlash}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.PLUGINS}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/popups" no-search>
         <settings-subpage page-title="$i18n{siteSettingsCategoryPopups}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.POPUPS}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/unsandboxedPlugins"
           no-search>
         <settings-subpage page-title="$i18n{siteSettingsUnsandboxedPlugins}">
+          <button class="icon-help subpage-title-extra"
+              is="paper-icon-button-light" on-tap="onHelpTap_"></button>
           <site-settings-category
               selected-site="{{selectedSite}}"
               category="{{ContentSettingsTypes.UNSANDBOXED_PLUGINS}}">
           </site-settings-category>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/usbDevices" no-search>
         <settings-subpage page-title="$i18n{siteSettingsUsbDevices}">
           <usb-devices></usb-devices>
         </settings-subpage>
       </template>
       <template is="dom-if" route-path="/siteSettings/siteDetails" no-search>
         <settings-subpage page-title="$i18n{siteSettingsSiteDetails}">
           <site-details site="[[selectedSite]]"></site-details>
         </settings-subpage>
       </template>
     </settings-animated-pages>
   </template>
   <script src="privacy_page.js"></script>
 </dom-module>