Chrome allows WebTouchPoint to store WebFloatPoint, instead of WebPoint.

content/renderer/input/input_handler_proxy.cc

 // Copyright 2013 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 "content/renderer/input/input_handler_proxy.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "content/renderer/input/input_handler_proxy_client.h"
@@ skipping 204 matching lines @@
     if (CancelCurrentFling(true))
       return DID_HANDLE;
     else if (!fling_may_be_active_on_main_thread_)
       return DROP_EVENT;
   } else if (event.type == WebInputEvent::TouchStart) {
     const WebTouchEvent& touch_event =
         *static_cast<const WebTouchEvent*>(&event);
     for (size_t i = 0; i < touch_event.touchesLength; ++i) {
       if (touch_event.touches[i].state != WebTouchPoint::StatePressed)
         continue;
-      if (input_handler_->HaveTouchEventHandlersAt(touch_event.touches[i]
-                                                       .position))
+      if (input_handler_->HaveTouchEventHandlersAt(
+              blink::WebPoint(touch_event.touches[i].position.x,
+                              touch_event.touches[i].position.y))) {
         return DID_NOT_HANDLE;
+      }
     }
     return DROP_EVENT;
   } else if (WebInputEvent::isKeyboardEventType(event.type)) {
     CancelCurrentFling(true);
   } else if (event.type == WebInputEvent::MouseMove) {
     const WebMouseEvent& mouse_event =
         *static_cast<const WebMouseEvent*>(&event);
     // TODO(tony): Ignore when mouse buttons are down?
     // TODO(davemoore): This should never happen, but bug #326635 showed some
     // surprising crashes.
@@ skipping 241 matching lines @@
   TRACE_EVENT2("renderer",
                "InputHandlerProxy::notifyCurrentFlingVelocity",
                "vx",
                velocity.width,
                "vy",
                velocity.height);
   input_handler_->NotifyCurrentFlingVelocity(ToClientScrollIncrement(velocity));
 }
 
 }  // namespace content