events: Change gesture-event handler in EventHandler to not return any values.

The EventHandler overriddes should mark the event as having been processed
(Event::SetHandled) when the event triggered an action, or stop the propagation
of the event (Event::StopPropagation) as appropriate (when the handler destroyed
the event-target, for example).

BUG=163618

Review URL: https://codereview.chromium.org/11280290

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170890 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 13 insertions, 9 deletions

diff --git a/ash/drag_drop/drag_drop_controller.cc b/ash/drag_drop/drag_drop_controller.cc
index db0e213..cf6135e 100644
--- a/ash/drag_drop/drag_drop_controller.cc
+++ b/ash/drag_drop/drag_drop_controller.cc
@@ -332,14 +332,17 @@ ui::EventResult DragDropController::OnTouchEvent(ui::TouchEvent* event) {
   return ui::ER_UNHANDLED;
 }
 
-ui::EventResult DragDropController::OnGestureEvent(ui::GestureEvent* event) {
+void DragDropController::OnGestureEvent(ui::GestureEvent* event) {
   if (!IsDragDropInProgress())
-    return ui::ER_UNHANDLED;
+    return;
 
   // If current drag session was not started by touch, dont process this touch
   // event, but consume it so it does not interfere with current drag session.
-  if (current_drag_event_source_ != ui::DragDropTypes::DRAG_EVENT_SOURCE_TOUCH)
-    return ui::ER_CONSUMED;
+  if (current_drag_event_source_ !=
+      ui::DragDropTypes::DRAG_EVENT_SOURCE_TOUCH) {
+    event->StopPropagation();
+    return;
+  }
 
   // Apply kTouchDragImageVerticalOffset to the location.
   ui::GestureEvent touch_offset_event(*event,
@@ -356,7 +359,8 @@ ui::EventResult DragDropController::OnGestureEvent(ui::GestureEvent* event) {
       drag_drop_tracker_->GetTarget(touch_offset_event);
   if (!translated_target) {
     DragCancel();
-    return ui::ER_HANDLED;
+    event->SetHandled();
+    return;
   }
   scoped_ptr<ui::LocatedEvent> translated_event(
       drag_drop_tracker_->ConvertEvent(translated_target, touch_offset_event));
@@ -384,7 +388,7 @@ ui::EventResult DragDropController::OnGestureEvent(ui::GestureEvent* event) {
     default:
       break;
   }
-  return ui::ER_HANDLED;
+  event->SetHandled();
 }
 
 void DragDropController::OnWindowDestroyed(aura::Window* window) {
diff --git a/ash/drag_drop/drag_drop_controller.h b/ash/drag_drop/drag_drop_controller.h
index f38b522..6fe58a1 100644
--- a/ash/drag_drop/drag_drop_controller.h
+++ b/ash/drag_drop/drag_drop_controller.h
@@ -68,7 +68,7 @@ class ASH_EXPORT DragDropController
   virtual ui::EventResult OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
   virtual ui::EventResult OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual ui::EventResult OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
-  virtual ui::EventResult OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
+  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // Overridden from aura::WindowObserver.
   virtual void OnWindowDestroyed(aura::Window* window) OVERRIDE;
diff --git a/ash/drag_drop/drag_drop_controller_unittest.cc b/ash/drag_drop/drag_drop_controller_unittest.cc
index 5847fdc..14a25c6 100644
--- a/ash/drag_drop/drag_drop_controller_unittest.cc
+++ b/ash/drag_drop/drag_drop_controller_unittest.cc
@@ -85,10 +85,10 @@ class DragTestView : public views::View {
     return true;
   }
 
-  ui::EventResult OnGestureEvent(ui::GestureEvent* event) OVERRIDE {
+  void OnGestureEvent(ui::GestureEvent* event) OVERRIDE {
     if (event->type() == ui::ET_GESTURE_LONG_TAP)
       long_tap_received_ = true;
-    return ui::ER_UNHANDLED;
+    return;
   }
 
   bool GetDropFormats(int* formats,