Add support for taking partial screenshot using touch

ash/wm/partial_screenshot_view.h

Index: ash/wm/partial_screenshot_view.h
diff --git a/ash/wm/partial_screenshot_view.h b/ash/wm/partial_screenshot_view.h
index a2ca607f2ff88e93c7b3ddcea03bb6c615c073e7..d334c557abec0e422b0f704cecddd02269714c21 100644
--- a/ash/wm/partial_screenshot_view.h
+++ b/ash/wm/partial_screenshot_view.h
@@ -38,6 +38,10 @@ class ASH_EXPORT PartialScreenshotView : public views::WidgetDelegateView {
   // Returns the currently selected region.
   gfx::Rect GetScreenshotRect() const;
 
+  void OnSelectionStarted(const gfx::Point& position);
+  void OnSelectionChanged(const gfx::Point& position);
+  void OnSelectionFinished();
+
   // Overridden from views::View:
   virtual gfx::NativeCursor GetCursor(const ui::MouseEvent& event) OVERRIDE;
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
@@ -45,6 +49,10 @@ class ASH_EXPORT PartialScreenshotView : public views::WidgetDelegateView {
   virtual bool OnMouseDragged(const ui::MouseEvent& event) OVERRIDE;
   virtual bool OnMouseWheel(const ui::MouseWheelEvent& event) OVERRIDE;
   virtual void OnMouseReleased(const ui::MouseEvent& event) OVERRIDE;
+  virtual void OnMouseCaptureLost() OVERRIDE;
+
+  // Overidden from ui::EventHandler:

[sky, 2013/03/26 14:43:35]

Isn't this overriden from View too?

[Yufeng Shen (Slow to review), 2013/03/26 15:35:14]

right, removed.

+  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   bool is_dragging_;
   gfx::Point start_position_;