Make RootView::DispatchGestureEvent() non-virtual

chrome/browser/ui/views/frame/browser_root_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 "chrome/browser/ui/views/frame/browser_root_view.h"
 
 #include "chrome/browser/autocomplete/autocomplete_classifier.h"
 #include "chrome/browser/autocomplete/autocomplete_classifier_factory.h"
 #include "chrome/browser/autocomplete/autocomplete_match.h"
 #include "chrome/browser/defaults.h"
@@ skipping 133 matching lines @@
       // tab-strip.
       if (scroll_offset > 0 && model->active_index() > 0) {
         chrome::SelectPreviousTab(browser);
         return true;
       }
     }
   }
   return RootView::OnMouseWheel(event);
 }
 
-void BrowserRootView::DispatchGestureEvent(ui::GestureEvent* event) {
-  if (event->type() == ui::ET_GESTURE_TAP &&
-      event->location().y() <= 0 &&
-      event->location().x() <= browser_view_->GetBounds().width()) {
-    TouchUMA::RecordGestureAction(TouchUMA::GESTURE_ROOTVIEWTOP_TAP);
+ui::EventDispatchDetails BrowserRootView::OnEventFromSource(ui::Event* event) {
+  if (event->IsGestureEvent()) {

[sky, 2014/07/15 20:53:11]

I'm not a fan of the static_casts all through out the code. They are easy to get
wrong. WDYT of isolating the static_cast in ui::Event:

ui::GestureEvent* AsGestureEvent() {
  return IsGestureEvent() ? static_cast<GestureEvent*>(this) : NULL;
}
? This code then becomes:

ui::GestureEvent* gesture_event = event->AsGestureEvent();
if (gesture_event) {....

[tdanderson, 2014/07/15 21:31:24]

Yes, I agree that isolating the static_casts in this manner would be a lot
nicer. But how about instead making IsGestureEvent() a precondition:

ui::GestureEvent* AsGestureEvent() {
  CHECK(IsGestureEvent());
  return static_cast<GestureEvent*>(this);
}

?

+    ui::GestureEvent* gesture_event = static_cast<ui::GestureEvent*>(event);
+    if (gesture_event->type() == ui::ET_GESTURE_TAP &&
+        gesture_event->location().y() <= 0 &&
+        gesture_event->location().x() <= browser_view_->GetBounds().width()) {
+      TouchUMA::RecordGestureAction(TouchUMA::GESTURE_ROOTVIEWTOP_TAP);
+    }
   }
 
-  RootView::DispatchGestureEvent(event);
+  return RootView::OnEventFromSource(event);
 }
 
 bool BrowserRootView::ShouldForwardToTabStrip(
     const ui::DropTargetEvent& event) {
   if (!tabstrip()->visible())
     return false;
 
   // Allow the drop as long as the mouse is over the tabstrip or vertically
   // before it.
   gfx::Point tab_loc_in_host;
@@ skipping 29 matching lines @@
       browser_view_->browser()->profile())->Classify(
           text, false, false, metrics::OmniboxEventProto::INVALID_SPEC, &match,
           NULL);
   if (!match.destination_url.is_valid())
     return false;
 
   if (url)
     *url = match.destination_url;
   return true;
 }