Account for failure of coordinate space transformations in browser

content/browser/renderer_host/render_widget_host_view_mac.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 #include <IOSurface/IOSurface.h>
 #include <stddef.h>
@@ skipping 323 matching lines @@
   // Returns true when we can do SurfaceHitTesting for the event type.
   bool ShouldRouteEvent(const blink::WebInputEvent& event) const;
   void ProcessMouseEvent(const blink::WebMouseEvent& event,
                          const ui::LatencyInfo& latency) override;
   void ProcessMouseWheelEvent(const blink::WebMouseWheelEvent& event,
                               const ui::LatencyInfo& latency) override;
   void ProcessTouchEvent(const blink::WebTouchEvent& event,
                          const ui::LatencyInfo& latency) override;
   void ProcessGestureEvent(const blink::WebGestureEvent& event,
                            const ui::LatencyInfo& latency) override;
-  gfx::Point TransformPointToLocalCoordSpace(
+  bool TransformPointToLocalCoordSpace(const gfx::Point& point,
+                                       const cc::SurfaceId& original_surface,
+                                       gfx::Point* transformed_point) override;
+  bool TransformPointToCoordSpaceForView(
       const gfx::Point& point,
-      const cc::SurfaceId& original_surface) override;
-  gfx::Point TransformPointToCoordSpaceForView(
-      const gfx::Point& point,
-      RenderWidgetHostViewBase* target_view) override;
+      RenderWidgetHostViewBase* target_view,
+      gfx::Point* transformed_point) override;
 
   // TextInputManager::Observer implementation.
   void OnUpdateTextInputStateCalled(TextInputManager* text_input_manager,
                                     RenderWidgetHostViewBase* updated_view,
                                     bool did_update_state) override;
   void OnImeCancelComposition(TextInputManager* text_input_manager,
                               RenderWidgetHostViewBase* updated_view) override;
   void OnImeCompositionRangeChanged(
       TextInputManager* text_input_manager,
       RenderWidgetHostViewBase* updated_view) override;
@@ skipping 197 matching lines @@
 
   // Factory used to safely scope delayed calls to ShutdownHost().
   base::WeakPtrFactory<RenderWidgetHostViewMac> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_