Bug 1199885 - Part 12: Add StartScrollbarDrag IPC message. r=kats

--HG--
extra : commitid : 87IsjW2NpRX

dom/ipc/PBrowser.ipdl

@@ -60,6 +60,7 @@ using mozilla::CommandInt from "mozilla/EventForwards.h";
 using mozilla::Modifiers from "mozilla/EventForwards.h";
 using mozilla::layers::GeckoContentController::APZStateChange from "mozilla/layers/GeckoContentController.h";
 using mozilla::WritingMode from "mozilla/WritingModes.h";
+using mozilla::layers::AsyncDragMetrics from "mozilla/layers/AsyncDragMetrics.h";
 using mozilla::layers::TouchBehaviorFlags from "mozilla/layers/APZUtils.h";
 using nsIWidget::TouchPointerState from "nsIWidget.h";
 using struct LookAndFeelInt from "mozilla/widget/WidgetMessageUtils.h";
@@ -545,6 +546,9 @@ parent:
     prio(high) sync DispatchMouseEvent(WidgetMouseEvent event);
     prio(high) sync DispatchKeyboardEvent(WidgetKeyboardEvent event);
 
+    // Start an APZ drag on a scrollbar
+    async StartScrollbarDrag(AsyncDragMetrics aDragMetrics);
+
     InvokeDragSession(IPCDataTransfer[] transfers, uint32_t action,
                       nsCString visualData, uint32_t width, uint32_t height,
                       uint32_t stride, uint8_t format, int32_t dragAreaX, int32_t dragAreaY);

dom/ipc/TabParent.cpp

@@ -26,6 +26,7 @@
 #include "mozilla/IMEStateManager.h"
 #include "mozilla/ipc/DocumentRendererParent.h"
 #include "mozilla/jsipc/CrossProcessObjectWrappers.h"
+#include "mozilla/layers/AsyncDragMetrics.h"
 #include "mozilla/layers/CompositorParent.h"
 #include "mozilla/layers/InputAPZContext.h"
 #include "mozilla/layout/RenderFrameParent.h"
@@ -3051,6 +3052,15 @@ TabParent::RecvSetTargetAPZC(const uint64_t& aInputBlockId,
   return true;
 }
 
+bool
+TabParent::RecvStartScrollbarDrag(const AsyncDragMetrics& aDragMetrics)
+{
+  if (RenderFrameParent* rfp = GetRenderFrame()) {
+    rfp->StartScrollbarDrag(aDragMetrics);
+  }
+  return true;
+}
+
 bool
 TabParent::RecvSetAllowedTouchBehavior(const uint64_t& aInputBlockId,
                                        nsTArray<TouchBehaviorFlags>&& aFlags)

dom/ipc/TabParent.h

@@ -44,6 +44,7 @@ class CpowHolder;
 } // namespace jsipc
 
 namespace layers {
+class AsyncDragMetrics;
 struct FrameMetrics;
 struct TextureFactoryIdentifier;
 } // namespace layers
@@ -83,6 +84,7 @@ class TabParent final : public PBrowserParent
                       , public nsIWebBrowserPersistable
 {
     typedef mozilla::dom::ClonedMessageData ClonedMessageData;
+    typedef mozilla::layers::AsyncDragMetrics AsyncDragMetrics;
 
     virtual ~TabParent();
 
@@ -243,6 +245,7 @@ public:
     virtual bool RecvDispatchWheelEvent(const mozilla::WidgetWheelEvent& aEvent) override;
     virtual bool RecvDispatchMouseEvent(const mozilla::WidgetMouseEvent& aEvent) override;
     virtual bool RecvDispatchKeyboardEvent(const mozilla::WidgetKeyboardEvent& aEvent) override;
+    virtual bool RecvStartScrollbarDrag(const AsyncDragMetrics& aDragMetrics) override;
 
     virtual PColorPickerParent*
     AllocPColorPickerParent(const nsString& aTitle, const nsString& aInitialColor) override;

layout/ipc/RenderFrameParent.cpp

@@ -597,6 +597,21 @@ RenderFrameParent::HitTest(const nsRect& aRect)
   return mTouchRegion.Contains(aRect);
 }
 
+void
+RenderFrameParent::StartScrollbarDrag(const AsyncDragMetrics& aDragMetrics)
+{
+  if (GetApzcTreeManager()) {
+    uint64_t layersId = GetLayersId();
+    ScrollableLayerGuid guid(layersId, aDragMetrics.mPresShellId,
+                             aDragMetrics.mViewId);
+
+    APZThreadUtils::RunOnControllerThread(
+      NewRunnableMethod(GetApzcTreeManager(),
+                        &APZCTreeManager::StartScrollbarDrag,
+                        guid, aDragMetrics));
+  }
+}
+
 void
 RenderFrameParent::GetTextureFactoryIdentifier(TextureFactoryIdentifier* aTextureFactoryIdentifier)
 {

layout/ipc/RenderFrameParent.h

@@ -25,6 +25,7 @@ class InputEvent;
 
 namespace layers {
 class APZCTreeManager;
+class AsyncDragMetrics;
 class TargetConfig;
 struct TextureFactoryIdentifier;
 struct ScrollableLayerGuid;
@@ -36,6 +37,7 @@ class RemoteContentController;
 
 class RenderFrameParent : public PRenderFrameParent
 {
+  typedef mozilla::layers::AsyncDragMetrics AsyncDragMetrics;
   typedef mozilla::layers::FrameMetrics FrameMetrics;
   typedef mozilla::layers::ContainerLayer ContainerLayer;
   typedef mozilla::layers::Layer Layer;
@@ -93,6 +95,8 @@ public:
 
   bool HitTest(const nsRect& aRect);
 
+  void StartScrollbarDrag(const AsyncDragMetrics& aDragMetrics);
+
   void GetTextureFactoryIdentifier(TextureFactoryIdentifier* aTextureFactoryIdentifier);
 
   inline uint64_t GetLayersId() { return mLayersId; }

widget/PuppetWidget.cpp

@@ -1141,6 +1141,12 @@ uint32_t PuppetWidget::GetMaxTouchPoints() const
   return sTouchPoints;
 }
 
+void
+PuppetWidget::StartAsyncScrollbarDrag(const AsyncDragMetrics& aDragMetrics)
+{
+  mTabChild->SendStartScrollbarDrag(aDragMetrics);
+}
+
 PuppetScreen::PuppetScreen(void *nativeScreen)
 {
 }

widget/PuppetWidget.h

@@ -251,6 +251,7 @@ public:
   virtual nsresult ClearNativeTouchSequence(nsIObserver* aObserver) override;
   virtual uint32_t GetMaxTouchPoints() const override;
 
+  virtual void StartAsyncScrollbarDrag(const AsyncDragMetrics& aDragMetrics) override;
 protected:
   bool mEnabled;
   bool mVisible;

widget/nsBaseWidget.cpp

@@ -1674,6 +1674,22 @@ nsBaseWidget::GetRootAccessible()
 
 #endif // ACCESSIBILITY
 
+void
+nsBaseWidget::StartAsyncScrollbarDrag(const AsyncDragMetrics& aDragMetrics)
+{
+  if (!AsyncPanZoomEnabled()) {
+    return;
+  }
+
+  MOZ_ASSERT(XRE_IsParentProcess() && mCompositorParent);
+
+  int layersId = mCompositorParent->RootLayerTreeId();;
+  ScrollableLayerGuid guid(layersId, aDragMetrics.mPresShellId, aDragMetrics.mViewId);
+
+  APZThreadUtils::RunOnControllerThread(
+    NewRunnableMethod(mAPZC.get(), &APZCTreeManager::StartScrollbarDrag, guid, aDragMetrics));
+}
+
 nsIntRect
 nsBaseWidget::GetScaledScreenBounds()
 {

widget/nsBaseWidget.h

@@ -312,6 +312,8 @@ public:
     return false;
   }
 
+  virtual void StartAsyncScrollbarDrag(const AsyncDragMetrics& aDragMetrics) override;
+
   /**
    * Use this when GetLayerManager() returns a BasicLayerManager
    * (nsBaseWidget::GetLayerManager() does). This sets up the widget's

widget/nsIWidget.h

@@ -49,6 +49,7 @@ namespace plugins {
 class PluginWidgetChild;
 } // namespace plugins
 namespace layers {
+class AsyncDragMetrics;
 class Composer2D;
 class Compositor;
 class CompositorChild;
@@ -316,6 +317,7 @@ class nsIWidget : public nsISupports {
   public:
     typedef mozilla::layers::Composer2D Composer2D;
     typedef mozilla::layers::CompositorChild CompositorChild;
+    typedef mozilla::layers::AsyncDragMetrics AsyncDragMetrics;
     typedef mozilla::layers::FrameMetrics FrameMetrics;
     typedef mozilla::layers::LayerManager LayerManager;
     typedef mozilla::layers::LayerManagerComposite LayerManagerComposite;
@@ -1676,6 +1678,8 @@ class nsIWidget : public nsISupports {
      */
     virtual bool CaptureWidgetOnScreen(mozilla::RefPtr<mozilla::gfx::DrawTarget> aDT) = 0;
 
+    virtual void StartAsyncScrollbarDrag(const AsyncDragMetrics& aDragMetrics) = 0;
+
 private:
   class LongTapInfo
   {