MacViews: Send Mac scrollWheel NSEvents as ui::ET_SCROLL (ui::ScrollEvent).

ui/views/cocoa/bridged_content_view.mm

 // Copyright 2014 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.
 
 #import "ui/views/cocoa/bridged_content_view.h"
 
 #include "base/logging.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 718 matching lines @@
 
 - (void)keyUp:(NSEvent*)theEvent {
   ui::KeyEvent event(theEvent);
   [self handleKeyEvent:&event];
 }
 
 - (void)scrollWheel:(NSEvent*)theEvent {
   if (!hostedView_)
     return;
 
-  ui::MouseWheelEvent event(theEvent);
-  hostedView_->GetWidget()->OnMouseEvent(&event);
+  ui::ScrollEvent event(theEvent);
+  hostedView_->GetWidget()->OnScrollEvent(&event);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // NSResponder Action Messages. Keep sorted according NSResponder.h (from the
 // 10.9 SDK). The list should eventually be complete. Anything not defined will
 // beep when interpretKeyEvents: would otherwise call it.
 // TODO(tapted): Make this list complete, except for insert* methods which are
 // dispatched as regular key events in doCommandBySelector:.
 
 // views::Textfields are single-line only, map Paragraph and Document commands
@@ skipping 605 matching lines @@
   }
 
   return [super accessibilityAttributeValue:attribute];
 }
 
 - (id)accessibilityHitTest:(NSPoint)point {
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
 @end