Adding four bezel gestures

ash/wm/system_gesture_event_filter.h

Index: ash/wm/system_gesture_event_filter.h
diff --git a/ash/wm/system_gesture_event_filter.h b/ash/wm/system_gesture_event_filter.h
index fe58711d7e1b350812e4f8072f267b70f8da20aa..f240691501eb26d0fe5eafc813e135b28fe50a51 100644
--- a/ash/wm/system_gesture_event_filter.h
+++ b/ash/wm/system_gesture_event_filter.h
@@ -18,6 +18,20 @@ class Window;
 namespace ash {
 namespace internal {
 
+enum BezelStart {
+  BEZEL_START_UNSET = 0,
+  BEZEL_START_TOP,
+  BEZEL_START_LEFT,
+  BEZEL_START_RIGHT,
+  BEZEL_START_BOTTOM
+};
+
+enum ScrollOrientation {
+  SCROLL_ORIENTATION_UNSET = 0,
+  SCROLL_ORIENTATION_HORIZONTAL,
+  SCROLL_ORIENTATION_VERTICAL
+};
+
 // An event filter which handles system level gesture events.
 class SystemGestureEventFilter : public aura::EventFilter {
  public:
@@ -36,6 +50,31 @@ class SystemGestureEventFilter : public aura::EventFilter {
       aura::GestureEvent* event) OVERRIDE;
 
  private:
+  // Handle events meant for volume / brightness. Returns true when no further
+  // events from this gesture should be sent.
+  bool HandleDeviceControl(aura::GestureEvent* event);
+
+  // Handle events meant for showing the launcher. Returns true when no further
+  // events from this gesture should be sent.
+  bool HandleLauncherControl(aura::GestureEvent* event);
+
+  // Handle events meant to switch through applications. Returns true when no
+  // further events from this gesture should be sent.
+  bool HandleApplicationControl(aura::GestureEvent* event);
+
+  // The percentage of the screen to the left and right which belongs to
+  // device gestures.
+  const int overlap_percent_;
+
+  // Which bezel corner are we on.
+  BezelStart start_location_;
+
+  // Which orientation are we moving.
+  ScrollOrientation orientation_;
+
+  // A device swipe gesture is in progress.
+  bool is_scrubbing_;
+
   DISALLOW_COPY_AND_ASSIGN(SystemGestureEventFilter);
 };