Bug 549223 - [E10s] MozAfterPaint events aren't activated when event listener is added to tabChildGlobal, r=bsmedberg

dom/base/nsPIWindowRoot.h

@@ -48,10 +48,10 @@ class nsIControllers;
 class nsIController;
 struct JSContext;
 
-// a9f58a8b-55cd-47fb-aeaa-f54010ffd154
+// 2e26a297-6e40-41c1-81c9-7306571f955e
 #define NS_IWINDOWROOT_IID \
-{ 0xa9f58a8b, 0x55cd, 0x47fb, \
-  { 0xae, 0xaa, 0xf5, 0x40, 0x10, 0xff, 0xd1, 0x54 } }
+{ 0x2e26a297, 0x6e40, 0x41c1, \
+  { 0x81, 0xc9, 0x73, 0x06, 0x57, 0x1f, 0x95, 0x5e } }
 
 class nsPIWindowRoot : public nsPIDOMEventTarget {
 public:
@@ -67,6 +67,7 @@ public:
   virtual nsresult GetControllers(nsIControllers** aResult) = 0;
 
   virtual void SetParentTarget(nsPIDOMEventTarget* aTarget) = 0;
+  virtual nsPIDOMEventTarget* GetParentTarget() = 0;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsPIWindowRoot, NS_IWINDOWROOT_IID)

dom/base/nsWindowRoot.h

@@ -102,6 +102,7 @@ public:
   {
     mParent = aTarget;
   }
+  virtual nsPIDOMEventTarget* GetParentTarget() { return mParent; }
 
   NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsWindowRoot, nsIDOMEventTarget)
 

dom/ipc/test.xul

@@ -164,6 +164,15 @@
       messageManager.addMessageListener("async-echo", echoListener);
       messageManager.sendAsyncMessage("async-echo");
     }
+
+    var MozAfterPaintCount = 0;
+    function enableMozAfterPaint() {
+      messageManager.addMessageListener("MozAfterPaint",
+        function(m) {
+          document.getElementById("messageLog").value = m.name + "[" + (++MozAfterPaintCount) + "]";
+        });
+      messageManager.loadFrameScript("data:,addEventListener('MozAfterPaint', function(e) { sendAsyncMessage('MozAfterPaint'); },true);", false);
+    }
   </script>
 
   <toolbar id="controls">
@@ -176,6 +185,7 @@
     <toolbarbutton onclick="randomClick()" label="random click"/>
     <toolbarbutton onclick="messageSpeed()" label="test message handling speed"/>
     <toolbarbutton onclick="listenerAddRemove()" label="test listener add/remove"/>
+    <toolbarbutton onclick="enableMozAfterPaint()" label="MozAfterPaint"/>
     <toolbarbutton onclick="openWindow()" label="open new window"/>
     <toolbarbutton onclick="closeWindow()" label="close this window"/>
   </toolbar>

layout/base/nsPresContext.cpp

@@ -105,6 +105,7 @@
 #endif // IBMBIDI
 
 #include "nsContentUtils.h"
+#include "nsPIWindowRoot.h"
 
 // Needed for Start/Stop of Image Animation
 #include "imgIContainer.h"
@@ -2068,7 +2069,12 @@ MayHavePaintEventListener(nsPIDOMWindow* aInnerWindow)
   if (manager && manager->MayHavePaintEventListener())
     return PR_TRUE;
 
-  return PR_FALSE;
+  nsCOMPtr<nsPIWindowRoot> root = do_QueryInterface(chromeEventHandler);
+  nsPIDOMEventTarget* tabChildGlobal;
+  return root &&
+         (tabChildGlobal = root->GetParentTarget()) &&
+         (manager = tabChildGlobal->GetListenerManager(PR_FALSE)) &&
+         manager->MayHavePaintEventListener();
 }
 
 PRBool