Do FinishAllRendering in WM_WINDOWPOSCHANGING

This ensures that the last swap completes before the window is resized, so that the window contents aren't scaled.

BUG=363704

Review URL: https://codereview.chromium.org/277053003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270206 0039d316-1c4b-4281-b951-d872f2087c98

ui/compositor/compositor.cc

@@ -90,7 +90,6 @@ Compositor::Compositor(gfx::AcceleratedWidget widget)
       device_scale_factor_(0.0f),
       last_started_frame_(0),
       last_ended_frame_(0),
-      next_draw_is_resize_(false),
       disable_schedule_composite_(false),
       compositor_lock_(NULL),
       defer_draw_scheduling_(false),
@@ -232,18 +231,6 @@ void Compositor::Draw() {
     // compositeImmediately() directly.
     Layout();
     host_->Composite(gfx::FrameTime::Now());
-
-#if defined(OS_WIN)
-    // While we resize, we are usually a few frames behind. By blocking
-    // the UI thread here we minize the area that is mis-painted, specially
-    // in the non-client area. See RenderWidgetHostViewAura::SetBounds for
-    // more details and bug 177115.
-    if (next_draw_is_resize_ && (last_ended_frame_ > 1)) {
-      next_draw_is_resize_ = false;
-      host_->FinishAllRendering();
-    }
-#endif
-
   }
   if (swap_state_ == SWAP_NONE)
     NotifyEnd();
@@ -257,6 +244,10 @@ void Compositor::ScheduleRedrawRect(const gfx::Rect& damage_rect) {
   host_->SetNeedsRedrawRect(damage_rect);
 }
 
+void Compositor::FinishAllRendering() {
+  host_->FinishAllRendering();
+}
+
 void Compositor::SetLatencyInfo(const ui::LatencyInfo& latency_info) {
   scoped_ptr<cc::SwapPromise> swap_promise(
       new cc::LatencyInfoSwapPromise(latency_info));
@@ -269,8 +260,6 @@ void Compositor::SetScaleAndSize(float scale, const gfx::Size& size_in_pixel) {
     size_ = size_in_pixel;
     host_->SetViewportSize(size_in_pixel);
     root_web_layer_->SetBounds(size_in_pixel);
-
-    next_draw_is_resize_ = true;
   }
   if (device_scale_factor_ != scale) {
     device_scale_factor_ = scale;

ui/compositor/compositor.h

@@ -172,6 +172,9 @@ class COMPOSITOR_EXPORT Compositor
   // from changes to layer properties.
   void ScheduleRedrawRect(const gfx::Rect& damage_rect);
 
+  // Finishes all outstanding rendering on the GPU.
+  void FinishAllRendering();
+
   void SetLatencyInfo(const LatencyInfo& latency_info);
 
   // Sets the compositor's device scale factor and size.
@@ -276,8 +279,6 @@ class COMPOSITOR_EXPORT Compositor
   int last_started_frame_;
   int last_ended_frame_;
 
-  bool next_draw_is_resize_;
-
   bool disable_schedule_composite_;
 
   CompositorLock* compositor_lock_;

ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc

@@ -907,6 +907,11 @@ bool DesktopWindowTreeHostWin::HandleScrollEvent(
   return event.handled();
 }
 
+void DesktopWindowTreeHostWin::HandleWindowSizeChanging() {
+  if (compositor())
+    compositor()->FinishAllRendering();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // DesktopWindowTreeHostWin, private:
 

ui/views/widget/desktop_aura/desktop_window_tree_host_win.h

@@ -204,6 +204,7 @@ class VIEWS_EXPORT DesktopWindowTreeHostWin
                              WPARAM w_param,
                              LPARAM l_param) OVERRIDE;
   virtual bool HandleScrollEvent(const ui::ScrollEvent& event) OVERRIDE;
+  virtual void HandleWindowSizeChanging() OVERRIDE;
 
   Widget* GetWidget();
   const Widget* GetWidget() const;

ui/views/win/hwnd_message_handler.cc

@@ -2224,6 +2224,9 @@ void HWNDMessageHandler::OnWindowPosChanging(WINDOWPOS* window_pos) {
     }
   }
 
+  if (DidClientAreaSizeChange(window_pos))
+    delegate_->HandleWindowSizeChanging();
+
   if (ScopedFullscreenVisibility::IsHiddenForFullscreen(hwnd())) {
     // Prevent the window from being made visible if we've been asked to do so.
     // See comment in header as to why we might want this.

ui/views/win/hwnd_message_handler_delegate.h

@@ -233,6 +233,9 @@ class VIEWS_EXPORT HWNDMessageHandlerDelegate {
   // handled by the delegate.
   virtual bool HandleScrollEvent(const ui::ScrollEvent& event) = 0;
 
+  // Called when the window size is about to change.
+  virtual void HandleWindowSizeChanging() = 0;
+
  protected:
   virtual ~HWNDMessageHandlerDelegate() {}
 };