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

ui/app_list/contents_view.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/app_list/contents_view.h"
 
 #include <algorithm>
 
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_view.h"
@@ skipping 167 matching lines @@
 
   if (abs(event.offset()) > kMinMouseWheelToSwitchPage) {
     if (!pagination_model_->has_transition())
       pagination_model_->SelectPageRelative(event.offset() > 0 ? -1 : 1, true);
     return true;
   }
 
   return false;
 }
 
-ui::EventResult ContentsView::OnGestureEvent(ui::GestureEvent* event) {
+void ContentsView::OnGestureEvent(ui::GestureEvent* event) {
   if (show_state_ != SHOW_APPS)
-    return ui::ER_UNHANDLED;
+    return;
 
   switch (event->type()) {
     case ui::ET_GESTURE_SCROLL_BEGIN:
       pagination_model_->StartScroll();
-      return ui::ER_CONSUMED;
+      event->SetHandled();
+      return;
     case ui::ET_GESTURE_SCROLL_UPDATE:
       // event->details.scroll_x() > 0 means moving contents to right. That is,
       // transitioning to previous page.
       pagination_model_->UpdateScroll(
           event->details().scroll_x() / GetContentsBounds().width());
-      return ui::ER_CONSUMED;
+      event->SetHandled();
+      return;
     case ui::ET_GESTURE_SCROLL_END:
       pagination_model_->EndScroll(pagination_model_->
           transition().progress < kFinishTransitionThreshold);
-      return ui::ER_CONSUMED;
+      event->SetHandled();
+      return;
     case ui::ET_SCROLL_FLING_START: {
       pagination_model_->EndScroll(true);
       if (fabs(event->details().velocity_x()) > kMinHorizVelocityToSwitchPage) {
         pagination_model_->SelectPageRelative(
             event->details().velocity_x() < 0 ? 1 : -1,
             true);
       }
-      return ui::ER_CONSUMED;
+      event->SetHandled();
+      return;
     }
     default:
       break;
   }
-
-  return ui::ER_UNHANDLED;
 }
 
 ui::EventResult ContentsView::OnScrollEvent(ui::ScrollEvent* event) {
   if (show_state_ != SHOW_APPS ||
       event->type() == ui::ET_SCROLL_FLING_CANCEL ||
       abs(event->x_offset()) < kMinScrollToSwitchPage) {
     return ui::ER_UNHANDLED;
   }
 
   if (!pagination_model_->has_transition()) {
     pagination_model_->SelectPageRelative(event->x_offset() > 0 ? -1 : 1,
                                           true);
   }
   return ui::ER_HANDLED;
 }
 
 }  // namespace app_list