Bug 595076 - App tab icons should be updated when the tab's favicon becomes available; r=dietrich a=blocking-betaN+

browser/base/content/tabview/groupitems.js

@@ -1481,18 +1481,55 @@ let GroupItems = {
   _inited: false,
   _activeGroupItem: null,
   _activeOrphanTab: null,
+  _cleanupFunctions: [],
 
   // ----------
   // Function: init
   init: function GroupItems_init() {
+    let self = this;
+
+    // setup attr modified handler, and prepare for its uninit
+    function handleAttrModified(xulTab) {
+      self._handleAttrModified(xulTab);
+    }
+
+    AllTabs.register("attrModified", handleAttrModified);
+    this._cleanupFunctions.push(function() {
+      AllTabs.unregister("attrModified", handleAttrModified);
+    });
   },
 
   // ----------
   // Function: uninit
   uninit : function GroupItems_uninit () {
+    this._cleanupFunctions.forEach(function(func) {
+      func();
+    });
+
+    this._cleanupFunctions = [];
+
     this.groupItems = null;
   },
 
+  // ----------
+  // watch for icon changes on app tabs
+  _handleAttrModified: function GroupItems__handleAttrModified(xulTab) {
+    if (xulTab.ownerDocument.defaultView != gWindow || !xulTab.pinned)
+      return;
+
+    let iconUrl = xulTab.image || Utils.defaultFaviconURL;
+    this.groupItems.forEach(function(groupItem) {
+      iQ(".appTabIcon", groupItem.$appTabTray).each(function(icon) {
+        let $icon = iQ(icon);
+        if ($icon.data("xulTab") != xulTab)
+          return;
+
+        if (iconUrl != $icon.attr("src"))
+          $icon.attr("src", iconUrl);
+      });
+    });
+  },
+
   // ----------
   // Function: getNextID
   // Returns the next unused groupItem ID.