Add APZ support for test.mousescroll callbacks. (bug 1142866 part 3, r=kats)

dom/ipc/PBrowser.ipdl

@@ -571,6 +571,11 @@ child:
              int32_t aModifiers,
              bool aPreventDefault);
 
+    /**
+     * APZ notification for mouse scroll testing events.
+     */
+    MouseScrollTestEvent(ViewID aScrollId, nsString aEvent);
+
     CompositionEvent(WidgetCompositionEvent event);
 
     SelectionEvent(WidgetSelectionEvent event);

dom/ipc/TabChild.cpp

@@ -2199,6 +2199,13 @@ TabChild::RecvMouseWheelEvent(const WidgetWheelEvent& aEvent,
   return true;
 }
 
+bool
+TabChild::RecvMouseScrollTestEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent)
+{
+  APZCCallbackHelper::NotifyMozMouseScrollEvent(aScrollId, aEvent);
+  return true;
+}
+
 static Touch*
 GetTouchForIdentifier(const WidgetTouchEvent& aEvent, int32_t aId)
 {

dom/ipc/TabChild.h

@@ -365,6 +365,8 @@ public:
                               const int32_t&  aCharCode,
                               const int32_t&  aModifiers,
                               const bool&     aPreventDefault) override;
+    virtual bool RecvMouseScrollTestEvent(const FrameMetrics::ViewID& aScrollId,
+                                          const nsString& aEvent) override;
     virtual bool RecvCompositionEvent(const mozilla::WidgetCompositionEvent& event) override;
     virtual bool RecvSelectionEvent(const mozilla::WidgetSelectionEvent& event) override;
     virtual bool RecvActivateFrameEvent(const nsString& aType, const bool& capture) override;

dom/ipc/TabParent.cpp

@@ -973,6 +973,14 @@ void TabParent::NotifyAPZStateChange(ViewID aViewId,
   }
 }
 
+void
+TabParent::NotifyMouseScrollTestEvent(const ViewID& aScrollId, const nsString& aEvent)
+{
+  if (!mIsDestroyed) {
+    unused << SendMouseScrollTestEvent(aScrollId, aEvent);
+  }
+}
+
 void
 TabParent::Activate()
 {

dom/ipc/TabParent.h

@@ -242,6 +242,7 @@ public:
     void NotifyAPZStateChange(ViewID aViewId,
                               APZStateChange aChange,
                               int aArg);
+    void NotifyMouseScrollTestEvent(const ViewID& aScrollId, const nsString& aEvent);
     void Activate();
     void Deactivate();
 

gfx/layers/apz/public/GeckoContentController.h

@@ -141,7 +141,6 @@ public:
     EndTouch,
     APZStateChangeSentinel
   };
-
   /**
    * General notices of APZ state changes for consumers.
    * |aGuid| identifies the APZC originating the state change.
@@ -153,6 +152,12 @@ public:
                                     APZStateChange aChange,
                                     int aArg = 0) {}
 
+  /**
+   * Notify content of a MozMouseScrollFailed event.
+   */
+  virtual void NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent)
+  {}
+
   GeckoContentController() {}
   virtual void Destroy() {}
 

gfx/layers/apz/src/AsyncPanZoomController.cpp

@@ -1476,6 +1476,21 @@ nsEventStatus AsyncPanZoomController::OnScrollWheel(const ScrollWheelInput& aEve
   double deltaX, deltaY;
   GetScrollWheelDelta(aEvent, deltaX, deltaY);
 
+  if ((deltaX || deltaY) &&
+      !CanScroll(deltaX, deltaY) &&
+      mInputQueue->GetCurrentWheelTransaction())
+  {
+    // We can't scroll this apz anymore, so we simply drop the event.
+    if (gfxPrefs::MouseScrollTestingEnabled()) {
+      if (nsRefPtr<GeckoContentController> controller = GetGeckoContentController()) {
+        controller->NotifyMozMouseScrollEvent(
+          mFrameMetrics.GetScrollId(),
+          NS_LITERAL_STRING("MozMouseScrollFailed"));
+      }
+    }
+    return nsEventStatus_eConsumeNoDefault;
+  }
+
   switch (aEvent.mScrollMode) {
     case ScrollWheelInput::SCROLLMODE_INSTANT: {
       // Decompose into pan events for simplicity.
@@ -1526,6 +1541,17 @@ nsEventStatus AsyncPanZoomController::OnScrollWheel(const ScrollWheelInput& aEve
   return nsEventStatus_eConsumeNoDefault;
 }
 
+void
+AsyncPanZoomController::NotifyMozMouseScrollEvent(const nsString& aString) const
+{
+  nsRefPtr<GeckoContentController> controller = GetGeckoContentController();
+  if (!controller) {
+    return;
+  }
+
+  controller->NotifyMozMouseScrollEvent(mFrameMetrics.GetScrollId(), aString);
+}
+
 nsEventStatus AsyncPanZoomController::OnPanMayBegin(const PanGestureInput& aEvent) {
   APZC_LOG("%p got a pan-maybegin in state %d\n", this, mState);
 

gfx/layers/apz/src/AsyncPanZoomController.h

@@ -369,6 +369,8 @@ public:
   // direction.
   bool CanScroll(double aDeltaX, double aDeltaY) const;
 
+  void NotifyMozMouseScrollEvent(const nsString& aString) const;
+
 protected:
   // Protected destructor, to discourage deletion outside of Release():
   ~AsyncPanZoomController();

gfx/layers/apz/src/InputBlockState.cpp

@@ -305,6 +305,11 @@ WheelBlockState::MaybeTimeout(const TimeStamp& aTimeStamp)
 
   TBS_LOG("%p wheel transaction timed out\n", this);
 
+  if (gfxPrefs::MouseScrollTestingEnabled()) {
+    nsRefPtr<AsyncPanZoomController> apzc = GetTargetApzc();
+    apzc->NotifyMozMouseScrollEvent(NS_LITERAL_STRING("MozMouseScrollTransactionTimeout"));
+  }
+
   EndTransaction();
   return true;
 }

gfx/layers/apz/src/InputQueue.cpp

@@ -170,7 +170,6 @@ InputQueue::ReceiveScrollWheelInput(const nsRefPtr<AsyncPanZoomController>& aTar
     }
   }
 
-  // If we have a block, it should be in a wheel transaction.
   MOZ_ASSERT(!block || block->InTransaction());
 
   if (!block) {

gfx/layers/apz/util/APZCCallbackHelper.cpp

@@ -666,6 +666,24 @@ APZCCallbackHelper::SendSetAllowedTouchBehaviorNotification(
   aCallback->Run(aInputBlockId, flags);
 }
 
+void
+APZCCallbackHelper::NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent)
+{
+  nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(aScrollId);
+  if (!targetContent) {
+    return;
+  }
+  nsCOMPtr<nsIDocument> ownerDoc = targetContent->OwnerDoc();
+  if (!ownerDoc) {
+    return;
+  }
+
+  nsContentUtils::DispatchTrustedEvent(
+    ownerDoc, targetContent,
+    aEvent,
+    true, true);
+}
+
 }
 }
 

gfx/layers/apz/util/APZCCallbackHelper.h

@@ -181,6 +181,9 @@ public:
                                                          const WidgetTouchEvent& aEvent,
                                                          uint64_t aInputBlockId,
                                                          const nsRefPtr<SetAllowedTouchBehaviorCallback>& aCallback);
+
+    /* Notify content of a mouse scroll testing event. */
+    static void NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent);
 };
 
 }

gfx/layers/apz/util/ChromeProcessController.cpp

@@ -199,4 +199,15 @@ ChromeProcessController::NotifyAPZStateChange(const ScrollableLayerGuid& aGuid,
   mAPZEventState->ProcessAPZStateChange(GetDocument(), aGuid.mScrollId, aChange, aArg);
 }
 
+void
+ChromeProcessController::NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent)
+{
+  if (MessageLoop::current() != mUILoop) {
+    mUILoop->PostTask(
+      FROM_HERE,
+      NewRunnableMethod(this, &ChromeProcessController::NotifyMozMouseScrollEvent, aScrollId, aEvent));
+    return;
+  }
 
+  APZCCallbackHelper::NotifyMozMouseScrollEvent(aScrollId, aEvent);
+}

gfx/layers/apz/util/ChromeProcessController.h

@@ -55,6 +55,8 @@ public:
   virtual void NotifyAPZStateChange(const ScrollableLayerGuid& aGuid,
                                     APZStateChange aChange,
                                     int aArg) override;
+  virtual void NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId,
+                                         const nsString& aEvent) override;
 private:
   nsCOMPtr<nsIWidget> mWidget;
   nsRefPtr<APZEventState> mAPZEventState;

gfx/thebes/gfxPrefs.h

@@ -339,7 +339,7 @@ private:
                                                                MouseWheelHasScrollDeltaOverride, bool, false);
   DECL_GFX_PREF(Live, "mousewheel.transaction.ignoremovedelay",MouseWheelIgnoreMoveDelayMs, int32_t, (int32_t)100);
   DECL_GFX_PREF(Live, "mousewheel.transaction.timeout",        MouseWheelTransactionTimeoutMs, int32_t, (int32_t)1500);
-
+  DECL_GFX_PREF(Live, "test.mousescroll",                      MouseScrollTestingEnabled, bool, false);
 
   DECL_GFX_PREF(Live, "nglayout.debug.widget_update_flashing", WidgetUpdateFlashing, bool, false);
   DECL_GFX_PREF(Live, "ui.click_hold_context_menus.delay",     UiClickHoldContextMenusDelay, int32_t, 500);

layout/ipc/RenderFrameParent.cpp

@@ -256,6 +256,20 @@ public:
     }
   }
 
+  void NotifyMozMouseScrollEvent(const FrameMetrics::ViewID& aScrollId, const nsString& aEvent) override {
+    if (MessageLoop::current() != mUILoop) {
+      mUILoop->PostTask(
+        FROM_HERE,
+        NewRunnableMethod(this, &RemoteContentController::NotifyMozMouseScrollEvent, aScrollId, aEvent));
+      return;
+    }
+
+    if (mRenderFrame) {
+      TabParent* browser = TabParent::GetFrom(mRenderFrame->Manager());
+      browser->NotifyMouseScrollTestEvent(aScrollId, aEvent);
+    }
+  }
+
   // Methods used by RenderFrameParent to set fields stored here.
 
   void SaveZoomConstraints(const ZoomConstraints& aConstraints)