Backed out changeset 50441cd0d6a1 (bug 1212321) for causing regressions

dom/apps/Webapps.js

@@ -573,6 +573,8 @@ WebappsApplication.prototype = {
 
   launch: function(aStartPoint) {
     let request = this.createRequest();
+    this.addMessageListeners(["Webapps:Launch:Return:OK",
+                              "Webapps:Launch:Return:KO"]);
     cpmm.sendAsyncMessage("Webapps:Launch", { origin: this.origin,
                                               manifestURL: this.manifestURL,
                                               startPoint: aStartPoint || "",
@@ -580,9 +582,6 @@ WebappsApplication.prototype = {
                                               topId: this._topId,
                                               timestamp: Date.now(),
                                               requestID: this.getRequestId(request) });
-    Services.obs.notifyObservers(null, "will-launch-app", null);
-    this.addMessageListeners(["Webapps:Launch:Return:OK",
-                              "Webapps:Launch:Return:KO"]);
     return request;
   },
 

dom/browser-element/BrowserElementChildPreload.js

@@ -27,10 +27,6 @@ XPCOMUtils.defineLazyModuleGetter(this, "ManifestObtainer",
 
 var kLongestReturnedString = 128;
 
-const Timer = Components.Constructor("@mozilla.org/timer;1",
-                                     "nsITimer",
-                                     "initWithCallback");
-
 function debug(msg) {
   //dump("BrowserElementChildPreload - " + msg + "\n");
 }
@@ -69,8 +65,7 @@ const OBSERVED_EVENTS = [
   'xpcom-shutdown',
   'audio-playback',
   'activity-done',
-  'invalid-widget',
-  'will-launch-app'
+  'invalid-widget'
 ];
 
 const COMMAND_MAP = {
@@ -337,14 +332,11 @@ BrowserElementChild.prototype = {
     this.forwarder.init();
   },
 
-  _paintFrozenTimer: null,
   observe: function(subject, topic, data) {
     // Ignore notifications not about our document.  (Note that |content| /can/
     // be null; see bug 874900.)
 
-    if (topic !== 'activity-done' &&
-        topic !== 'audio-playback' &&
-        topic !== 'will-launch-app' &&
+    if (topic !== 'activity-done' && topic !== 'audio-playback' &&
         (!content || subject !== content.document)) {
       return;
     }
@@ -365,26 +357,9 @@ BrowserElementChild.prototype = {
       case 'invalid-widget':
         sendAsyncMsg('error', { type: 'invalid-widget' });
         break;
-      case 'will-launch-app':
-        // If the launcher is not visible, let's ignore the message.
-        if (!docShell.isActive) {
-          return;
-        }
-
-        docShell.contentViewer.pausePainting();
-
-        this._paintFrozenTimer && this._paintFrozenTimer.cancel();
-        this._paintFrozenTimer = new Timer(this, 3000, Ci.nsITimer.TYPE_ONE_SHOT);
-        break;
     }
   },
 
-  notify: function(timer) {
-    docShell.contentViewer.resumePainting();
-    this._paintFrozenTimer.cancel();
-    this._paintFrozenTimer = null;
-  },
-
   /**
    * Called when our TabChildGlobal starts to die.  This is not called when the
    * page inside |content| unloads.
@@ -1403,11 +1378,6 @@ BrowserElementChild.prototype = {
     if (docShell && docShell.isActive !== visible) {
       docShell.isActive = visible;
       sendAsyncMsg('visibilitychange', {visible: visible});
-
-      // Ensure painting is not frozen if the app goes visible.
-      if (visible && this._paintFrozenTimer) {
-        this.notify();
-      }
     }
   },