MD Settings: Allow deleting read-only content setting exceptions.

chrome/browser/resources/settings/site_settings/site_list.html

 <link rel="import" href="chrome://resources/cr_elements/cr_action_menu/cr_action_menu.html">
 <link rel="import" href="chrome://resources/cr_elements/icons.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-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="../i18n_setup.html">
 <link rel="import" href="../icons.html">
 <link rel="import" href="../route.html">
 <link rel="import" href="../settings_shared_css.html">
@@ skipping 63 matching lines @@
 
               <!-- This div must not contain extra whitespace. -->
               <div class="selectable secondary text-elide" id="siteDescription"
                   >[[computeSiteDescription_(item)]]</div>
             </div>
 
             <template is="dom-if" if="[[!!computeIconControlledBy_(item)]]">
               <iron-icon icon="[[computeIconControlledBy_(item)]]"></iron-icon>
             </template>
 
-            <paper-icon-button id="dots" icon="cr:more-vert"
+            <paper-icon-button id="resetSite" icon="cr:delete"
+                hidden="[[!readOnlyList]]" on-tap="onResetButtonTap_"

[dschuyler, 2017/03/22 18:33:08]

What will happen if this is policy enforced?
I looks like we might show the delete icon in that case and it seems like we
should not.

[tommycli, 2017/03/22 21:05:37]

Done.

+                alt="$i18n{siteSettingsActionReset}">
+            </paper-icon-button>
+            <paper-icon-button id="actionMenuButton" icon="cr:more-vert"

[dschuyler, 2017/03/22 18:33:08]

FYI (doesn't necessarily require a change)

I'm not saying that "dots" is a great id name, but let me point out this style
guide entry:
https://google.github.io/styleguide/htmlcssguide.html#ID_and_Class_Name_Style
(I believe the issue here is size, since the label is not compiled away like it
would be in C++ (which calls for more verbose names)).

[tommycli, 2017/03/22 21:05:37]

Acknowledged.

                 hidden="[[isActionMenuHidden_(item.source, readOnlyList)]]"
                 on-tap="onShowActionMenuTap_" title="$i18n{moreActions}">
             </paper-icon-button>
             <template is="dom-if" if="[[enableSiteSettings_]]">
               <div on-tap="onOriginTap_" actionable>
                 <button class="subpage-arrow" is="paper-icon-button-light"
                     aria-label$="[[item.displayName]]"
                     aria-describedby="siteDescription"></button>
               </div>
             </template>
           </div>
         </template>
       </div>
     </div>
     <template is="dom-if" if="[[showEditExceptionDialog_]]" restamp>
       <settings-edit-exception-dialog model="[[actionMenuSite_]]"
           on-close="onEditExceptionDialogClosed_">
       </settings-edit-exception-dialog>
     </template>
   </template>
   <script src="site_list.js"></script>
 </dom-module>