Block internal PlatformEvents before they are dispatched in touchview.

ui/events/x/events_x.cc

Index: ui/events/x/events_x.cc
diff --git a/ui/events/x/events_x.cc b/ui/events/x/events_x.cc
index 9d6b15a2eca3a0dc71a833999707b1385c79e011..e9198083a831c6b994c119c0d9de574862aafd51 100644
--- a/ui/events/x/events_x.cc
+++ b/ui/events/x/events_x.cc
@@ -268,6 +268,11 @@ void UpdateDeviceList() {
 }
 
 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;