diff --git a/layout/base/nsIPresShell.h b/layout/base/nsIPresShell.h
index aec4b76aa252..d3f7c84e7473 100644
--- a/layout/base/nsIPresShell.h
+++ b/layout/base/nsIPresShell.h
@@ -114,10 +114,10 @@ typedef struct CapturingContentInfo {
   nsIContent* mContent;
 } CapturingContentInfo;
 
-// f50f99bc-e178-4e67-89ea-f2aee5923f6d
+// 307910dd-7355-4535-84e7-6b95a4edffbe
 #define NS_IPRESSHELL_IID \
-{ 0xf50f99bc, 0xe178, 0x4e67, \
-  { 0x89, 0xea, 0xf2, 0xae, 0xe5, 0x92, 0x3f, 0x6d } }
+{ 0x307910dd, 0x7355, 0x4535, \
+  { 0x84, 0xe7, 0x6b, 0x95, 0xa4, 0xed, 0xff, 0xbe } }
 
 // debug VerifyReflow flags
 #define VERIFY_REFLOW_ON                    0x01
@@ -1252,12 +1252,6 @@ public:
    * widget geometry.
    */
   virtual void WillPaint(bool aWillSendDidPaint) = 0;
-  /**
-   * Notify that we called Paint with PAINT_LAYERS. Only fires on the
-   * pres shell for the painted widget. This is issued at a time when it's
-   * safe to modify widget geometry.
-   */
-  virtual void DidPaint() = 0;
   /**
    * Notify that we're going to call Paint with PAINT_COMPOSITE.
    * Fires on the presshell for the painted widget.
diff --git a/layout/base/nsPresShell.cpp b/layout/base/nsPresShell.cpp
index 0d7c6b1e852b..94fed124654f 100644
--- a/layout/base/nsPresShell.cpp
+++ b/layout/base/nsPresShell.cpp
@@ -7042,11 +7042,6 @@ PresShell::WillPaint(bool aWillSendDidPaint)
   FlushPendingNotifications(Flush_InterruptibleLayout);
 }
 
-void
-PresShell::DidPaint()
-{
-}
-
 void
 PresShell::WillPaintWindow(bool aWillSendDidPaint)
 {
diff --git a/layout/base/nsPresShell.h b/layout/base/nsPresShell.h
index 55ef4b3a73ec..f31364eb379e 100644
--- a/layout/base/nsPresShell.h
+++ b/layout/base/nsPresShell.h
@@ -196,7 +196,6 @@ public:
                                                         nsEventStatus* aStatus);
   virtual bool ShouldIgnoreInvalidation();
   virtual void WillPaint(bool aWillSendDidPaint);
-  virtual void DidPaint();
   virtual void WillPaintWindow(bool aWillSendDidPaint);
   virtual void DidPaintWindow();
   virtual void ScheduleViewManagerFlush();
diff --git a/view/src/nsViewManager.cpp b/view/src/nsViewManager.cpp
index 706f3ca46e6d..9076d36446dd 100644
--- a/view/src/nsViewManager.cpp
+++ b/view/src/nsViewManager.cpp
@@ -714,10 +714,6 @@ void nsViewManager::DidPaintWindow()
   if (shell) {
     shell->DidPaintWindow();
   }
-
-  if (!IsRefreshDriverPaintingEnabled()) {
-    mRootViewManager->CallDidPaintOnObserver();
-  }
 }
 
 nsresult nsViewManager::DispatchEvent(nsGUIEvent *aEvent, nsIView* aView, nsEventStatus* aStatus)
@@ -1214,7 +1210,6 @@ nsViewManager::ProcessPendingUpdates()
       CallWillPaintOnObservers(true);
     }
     ProcessPendingUpdatesForView(mRootView, true);
-    CallDidPaintOnObserver();
   } else {
     ProcessPendingUpdatesForView(mRootView, true);
   }
@@ -1259,19 +1254,6 @@ nsViewManager::CallWillPaintOnObservers(bool aWillSendDidPaint)
   }
 }
 
-void
-nsViewManager::CallDidPaintOnObserver()
-{
-  NS_PRECONDITION(IsRootVM(), "Must be root VM for this to be called!");
-
-  if (mRootView && mRootView->IsEffectivelyVisible()) {
-    nsCOMPtr<nsIPresShell> shell = GetPresShell();
-    if (shell) {
-      shell->DidPaint();
-    }
-  }
-}
-
 NS_IMETHODIMP
 nsViewManager::GetLastUserEventTime(uint32_t& aTime)
 {
diff --git a/view/src/nsViewManager.h b/view/src/nsViewManager.h
index 9a22a9e96a3f..4f743f6fc81c 100644
--- a/view/src/nsViewManager.h
+++ b/view/src/nsViewManager.h
@@ -121,7 +121,6 @@ private:
    * Call WillPaint() on all view observers under this vm root.
    */
   void CallWillPaintOnObservers(bool aWillSendDidPaint);
-  void CallDidPaintOnObserver();
   void ReparentChildWidgets(nsIView* aView, nsIWidget *aNewWidget);
   void ReparentWidgets(nsIView* aView, nsIView *aParent);
   void InvalidateWidgetArea(nsView *aWidgetView, const nsRegion &aDamagedRegion);