Block internal PlatformEvents before they are dispatched in touchview.

ui/events/x/events_x.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/events/event_constants.h"
 
 #include <cmath>
 #include <string.h>
 #include <X11/extensions/XInput.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 250 matching lines @@
 namespace ui {
 
 void UpdateDeviceList() {
   XDisplay* display = gfx::GetXDisplay();
   DeviceListCacheX::GetInstance()->UpdateDeviceList(display);
   TouchFactory::GetInstance()->UpdateDeviceList(display);
   DeviceDataManager::GetInstance()->UpdateDeviceList(display);
 }
 
 EventType EventTypeFromNative(const base::NativeEvent& native_event) {
+  // Allow the DeviceDataManager to block the event. If blocked return
+  // ET_UNKNOWN as the type so this event will not be further processed.
+  if (DeviceDataManager::GetInstance()->EventBlocked(native_event))
+    return ET_UNKNOWN;
+
   switch (native_event->type) {
     case KeyPress:
       return ET_KEY_PRESSED;
     case KeyRelease:
       return ET_KEY_RELEASED;
     case ButtonPress:
       if (static_cast<int>(native_event->xbutton.button) >= kMinWheelButton &&
           static_cast<int>(native_event->xbutton.button) <= kMaxWheelButton)
         return ET_MOUSEWHEEL;
       return ET_MOUSE_PRESSED;
@@ skipping 440 matching lines @@
   DeviceDataManager::GetInstance()->GetGestureTimes(
       native_event, start_time, end_time);
   return true;
 }
 
 bool IsTouchpadEvent(const base::NativeEvent& event) {
   return DeviceDataManager::GetInstance()->IsTouchpadXInputEvent(event);
 }
 
 }  // namespace ui