Use active state on touch start for tray icons

ash/system/tray/tray_background_view.h

Index: ash/system/tray/tray_background_view.h
diff --git a/ash/system/tray/tray_background_view.h b/ash/system/tray/tray_background_view.h
index da4eaf547ce28d0d34e9b4df2c69263aab9cf3bb..a17a01497b8ee37dd7568b65b318dd32981f1c3d 100644
--- a/ash/system/tray/tray_background_view.h
+++ b/ash/system/tray/tray_background_view.h
@@ -8,6 +8,7 @@
 #include "ash/ash_export.h"
 #include "ash/shelf/background_animator.h"
 #include "ash/shelf/shelf_types.h"
+#include "ash/shell_observer.h"
 #include "ash/system/tray/actionable_view.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/views/bubble/tray_bubble_view.h"
@@ -25,7 +26,8 @@ class TrayBackground;
 // items can override PerformAction when clicked on.
 class ASH_EXPORT TrayBackgroundView : public ActionableView,
                                       public BackgroundAnimatorDelegate,
-                                      public ui::ImplicitAnimationObserver {
+                                      public ui::ImplicitAnimationObserver,
+                                      public ShellObserver {
  public:
   static const char kViewClassName[];
 
@@ -77,10 +79,15 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // ActionableView:
   virtual bool PerformAction(const ui::Event& event) OVERRIDE;
   virtual gfx::Rect GetFocusBounds() OVERRIDE;
+  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // BackgroundAnimatorDelegate:
   virtual void UpdateBackground(int alpha) OVERRIDE;
 
+  // ShellObserver:
+  virtual void OnMaximizeModeStarted() OVERRIDE;
+  virtual void OnMaximizeModeEnded() OVERRIDE;
+
   // Called whenever the shelf alignment changes.
   virtual void SetShelfAlignment(ShelfAlignment alignment);
 
@@ -185,6 +192,10 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // differently if set to true.
   bool draw_background_as_active_;
 
+  // True if maximize mode is enabled, and touch view feedback has been enabled.
+  // When enabled touch gestures will toggle rendering the background as active.
+  bool touch_feedback_enabled_;
+
   scoped_ptr<TrayWidgetObserver> widget_observer_;
   scoped_ptr<TrayEventFilter> tray_event_filter_;