Mojom: Blanket change to mark all pointer/handle fields as nullable.

mojo/services/public/interfaces/input_events/input_events.mojom

 // 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 "mojo/services/public/interfaces/geometry/geometry.mojom"
 import "mojo/services/public/interfaces/input_events/input_event_constants.mojom"
 import "mojo/services/public/interfaces/input_events/input_key_codes.mojom"
 
 module mojo {
 
 struct LocationData {
-  Point in_view_location;
+  Point? in_view_location;
   Point? screen_location;
 };
 
 struct KeyData {
   // The chromium event key code; these values are from the ui/ KeyCode enum,
   // which has the fun property of being neither consistently the Windows key
   // code, nor the X11 keycodes. (This value is consistent across platforms
   // for basic ASCII characters; it will differ for modifiers. We don't define
   // this as a mojo enum because mojom doesn't appear to have a platform
   // dependent preprocessor yet.)
@@ skipping 37 matching lines @@
   EventType action;
   EventFlags flags;
   int64 time_stamp;
   LocationData? location_data;
   KeyData? key_data;
   TouchData? touch_data;
   MouseWheelData? wheel_data;
 };
 
 }