Bug 1143518 - Remove the TryCapture path which is now obsolete. r=smaug

dom/ipc/TabParent.cpp

@@ -236,8 +236,6 @@ private:
 namespace mozilla {
 namespace dom {
 
-TabParent* sEventCapturer;
-
 TabParent *TabParent::mIMETabParent = nullptr;
 TabParent::LayerToTabParentTable* TabParent::sLayerToTabParentTable = nullptr;
 
@@ -262,7 +260,6 @@ TabParent::TabParent(nsIContentParent* aManager,
   , mIMECompositionStart(0)
   , mIMESeqno(0)
   , mIMECompositionRectOffset(0)
-  , mEventCaptureDepth(0)
   , mRect(0, 0, 0, 0)
   , mDimensions(0, 0)
   , mOrientation(0)
@@ -401,9 +398,6 @@ TabParent::Recv__delete__()
 void
 TabParent::ActorDestroy(ActorDestroyReason why)
 {
-  if (sEventCapturer == this) {
-    sEventCapturer = nullptr;
-  }
   if (mIMETabParent == this) {
     mIMETabParent = nullptr;
   }
@@ -1325,22 +1319,7 @@ bool TabParent::SendRealTouchEvent(WidgetTouchEvent& event)
     return false;
   }
   if (event.message == NS_TOUCH_START) {
-    // Adjust the widget coordinates to be relative to our frame.
-    nsRefPtr<nsFrameLoader> frameLoader = GetFrameLoader();
-    if (!frameLoader) {
-      // No frame anymore?
-      sEventCapturer = nullptr;
-      return false;
-    }
-
     mChildProcessOffsetAtTouchStart = GetChildProcessOffset();
-
-    MOZ_ASSERT((!sEventCapturer && mEventCaptureDepth == 0) ||
-               (sEventCapturer == this && mEventCaptureDepth > 0));
-    // We want to capture all remaining touch events in this series
-    // for fast-path dispatch.
-    sEventCapturer = this;
-    ++mEventCaptureDepth;
   }
 
   // PresShell::HandleEventInternal adds touches on touch end/cancel.  This
@@ -1373,41 +1352,6 @@ bool TabParent::SendRealTouchEvent(WidgetTouchEvent& event)
     PBrowserParent::SendRealTouchEvent(event, guid, blockId);
 }
 
-/*static*/ TabParent*
-TabParent::GetEventCapturer()
-{
-  return sEventCapturer;
-}
-
-bool
-TabParent::TryCapture(const WidgetGUIEvent& aEvent)
-{
-  MOZ_ASSERT(sEventCapturer == this && mEventCaptureDepth > 0);
-
-  if (aEvent.mClass != eTouchEventClass) {
-    // Only capture of touch events is implemented, for now.
-    return false;
-  }
-
-  WidgetTouchEvent event(*aEvent.AsTouchEvent());
-
-  bool isTouchPointUp = (event.message == NS_TOUCH_END ||
-                         event.message == NS_TOUCH_CANCEL);
-  if (event.message == NS_TOUCH_START || isTouchPointUp) {
-    // Let the DOM see touch start/end events so that its touch-point
-    // state stays consistent.
-    if (isTouchPointUp && 0 == --mEventCaptureDepth) {
-      // All event series are un-captured, don't try to catch any
-      // more.
-      sEventCapturer = nullptr;
-    }
-    return false;
-  }
-
-  SendRealTouchEvent(event);
-  return true;
-}
-
 bool
 TabParent::RecvSyncMessage(const nsString& aMessage,
                            const ClonedMessageData& aData,
@@ -2550,11 +2494,6 @@ TabParent::GetLoadContext()
   return loadContext.forget();
 }
 
-/* Be careful if you call this method while proceding a real touch event. For
- * example sending a touchstart during a real touchend may results into
- * a busted mEventCaptureDepth and following touch events may not do what you
- * expect.
- */
 NS_IMETHODIMP
 TabParent::InjectTouchEvent(const nsAString& aType,
                             uint32_t* aIdentifiers,
@@ -2614,11 +2553,6 @@ TabParent::InjectTouchEvent(const nsAString& aType,
     event.touches.AppendElement(t);
   }
 
-  if ((msg == NS_TOUCH_END || msg == NS_TOUCH_CANCEL) && sEventCapturer) {
-    WidgetGUIEvent* guiEvent = event.AsGUIEvent();
-    TryCapture(*guiEvent);
-  }
-
   SendRealTouchEvent(event);
   return NS_OK;
 }

dom/ipc/TabParent.h

@@ -102,30 +102,6 @@ public:
 
     nsIXULBrowserWindow* GetXULBrowserWindow();
 
-    /**
-     * Return the TabParent that has decided it wants to capture an
-     * event series for fast-path dispatch to its subprocess, if one
-     * has.
-     *
-     * DOM event dispatch and widget are free to ignore capture
-     * requests from TabParents; the end result wrt remote content is
-     * (must be) always the same, albeit usually slower without
-     * subprocess capturing.  This allows frontends/widget backends to
-     * "opt in" to faster cross-process dispatch.
-     */
-    static TabParent* GetEventCapturer();
-    /**
-     * If this is the current event capturer, give this a chance to
-     * capture the event.  If it was captured, return true, false
-     * otherwise.  Un-captured events should follow normal DOM
-     * dispatch; captured events should result in no further
-     * processing from the caller of TryCapture().
-     *
-     * It's an error to call TryCapture() if this isn't the event
-     * capturer.
-     */
-    bool TryCapture(const WidgetGUIEvent& aEvent);
-
     void Destroy();
 
     virtual bool RecvMoveFocus(const bool& aForward) MOZ_OVERRIDE;
@@ -440,9 +416,6 @@ protected:
     LayoutDeviceIntRect mIMECaretRect;
     LayoutDeviceIntRect mIMEEditorRect;
 
-    // The number of event series we're currently capturing.
-    int32_t mEventCaptureDepth;
-
     nsIntRect mRect;
     ScreenIntSize mDimensions;
     ScreenOrientation mOrientation;

gfx/layers/apz/util/APZCCallbackHelper.cpp

@@ -415,23 +415,10 @@ APZCCallbackHelper::ApplyCallbackTransform(WidgetTouchEvent& aEvent,
 nsEventStatus
 APZCCallbackHelper::DispatchWidgetEvent(WidgetGUIEvent& aEvent)
 {
-  if (!aEvent.widget)
-    return nsEventStatus_eConsumeNoDefault;
-
-  // A nested process may be capturing events.
-  if (TabParent* capturer = TabParent::GetEventCapturer()) {
-    if (capturer->TryCapture(aEvent)) {
-      // Only touch events should be captured, and touch events from a parent
-      // process should not make it here. Capture for those is done elsewhere
-      // (for gonk, in nsWindow::DispatchTouchInputViaAPZ).
-      MOZ_ASSERT(!XRE_IsParentProcess());
-
-      return nsEventStatus_eConsumeNoDefault;
-    }
+  nsEventStatus status = nsEventStatus_eConsumeNoDefault;
+  if (aEvent.widget) {
+    aEvent.widget->DispatchEvent(&aEvent, status);
   }
-  nsEventStatus status;
-  NS_ENSURE_SUCCESS(aEvent.widget->DispatchEvent(&aEvent, status),
-                    nsEventStatus_eConsumeNoDefault);
   return status;
 }
 

widget/gonk/nsWindow.cpp

@@ -317,24 +317,10 @@ nsWindow::DispatchTouchEventForAPZ(const MultiTouchInput& aInput,
     // Convert it to an event we can send to Gecko
     WidgetTouchEvent event = aInput.ToWidgetTouchEvent(this);
 
-    // If there is an event capturing child process, send it directly there.
-    // This happens if we already sent a touchstart event through the root
-    // process hit test and it ended up going to a child process. The event
-    // capturing process should get all subsequent touch events in the same
-    // event block. In this case the TryCapture call below will return true,
-    // and the child process will take care of responding to the event as needed
-    // so we don't need to do anything else here.
-    if (TabParent* capturer = TabParent::GetEventCapturer()) {
-        InputAPZContext context(aGuid, aInputBlockId);
-        if (capturer->TryCapture(event)) {
-            return;
-        }
-    }
-
-    // If it didn't get captured, dispatch the event into the gecko root process
-    // for "normal" flow. The event might get sent to the child process still,
-    // but if it doesn't we need to notify the APZ of various things. All of
-    // that happens in DispatchEventForAPZ
+    // Dispatch the event into the gecko root process for "normal" flow.
+    // The event might get sent to a child process, but if it doesn't we need to
+    // notify the APZ of various things. All of that happens in
+    // ProcessUntransformedAPZEvent
     ProcessUntransformedAPZEvent(&event, aGuid, aInputBlockId);
 }