Proper MouseEvent targeting. Adds a Window method that locates a Window for a given point.

aura/demo/demo_main.cc

Index: aura/demo/demo_main.cc
===================================================================
--- aura/demo/demo_main.cc	(revision 98852)
+++ aura/demo/demo_main.cc	(working copy)
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "aura/desktop.h"
+#include "aura/event.h"
 #include "aura/window.h"
 #include "aura/window_delegate.h"
 #include "base/at_exit.h"
@@ -12,7 +13,6 @@
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
-#include "ui/gfx/canvas.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/rect.h"
 
@@ -23,10 +23,17 @@
  public:
   explicit DemoWindowDelegate(SkColor color) : color_(color) {}
 
+  virtual bool OnMouseEvent(const aura::MouseEvent& event) OVERRIDE {
+    return true;
+  }
+
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
     canvas->AsCanvasSkia()->drawColor(color_, SkXfermode::kSrc_Mode);
   }
 
+  virtual void OnWindowDestroyed() OVERRIDE {
+  }
+
  private:
   SkColor color_;