WebMouseEvent coordinates are now fractional & private

content/browser/renderer_host/input/web_input_event_builders_mac.mm

 // Copyright 2015 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.
 
 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006-2009 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ skipping 97 matching lines @@
     modifiers |= blink::WebInputEvent::MiddleButtonDown;
 
   return modifiers;
 }
 
 void SetWebEventLocationFromEventInView(blink::WebMouseEvent* result,
                                         NSEvent* event,
                                         NSView* view) {
   NSPoint screen_local = ui::ConvertPointFromWindowToScreen(
       [view window], [event locationInWindow]);
-  result->globalX = screen_local.x;
-  // Flip y.
   NSScreen* primary_screen = ([[NSScreen screens] count] > 0)
                                  ? [[NSScreen screens] firstObject]
                                  : nil;
-  if (primary_screen)
-    result->globalY = [primary_screen frame].size.height - screen_local.y;
-  else
-    result->globalY = screen_local.y;
+  // Flip y conditionally.
+  result->setPositionInScreen(
+      screen_local.x, primary_screen
+                          ? [primary_screen frame].size.height - screen_local.y
+                          : screen_local.y);
 
   NSPoint content_local =
       [view convertPoint:[event locationInWindow] fromView:nil];
-  result->x = content_local.x;
-  result->y = [view frame].size.height - content_local.y;  // Flip y.
+  // Flip y.
+  result->setPositionInWidget(content_local.x,
+                              [view frame].size.height - content_local.y);
 
   result->movementX = [event deltaX];
   result->movementY = [event deltaY];
 }
 
 bool IsSystemKeyEvent(const blink::WebKeyboardEvent& event) {
   // Windows and Linux set |isSystemKey| if alt is down. Blink looks at this
   // flag to decide if it should handle a key or not. E.g. alt-left/right
   // shouldn't be used by Blink to scroll the current page, because we want
   // to get that key back for it to do history navigation. Hence, the
@@ skipping 358 matching lines @@
 }
 
 blink::WebGestureEvent WebGestureEventBuilder::Build(NSEvent* event,
                                                      NSView* view) {
   blink::WebGestureEvent result;
 
   // Use a temporary WebMouseEvent to get the location.
   blink::WebMouseEvent temp;
 
   SetWebEventLocationFromEventInView(&temp, event, view);
-  result.x = temp.x;
-  result.y = temp.y;
-  result.globalX = temp.globalX;
-  result.globalY = temp.globalY;
+  result.x = temp.positionInWidget().x;
+  result.y = temp.positionInWidget().y;
+  result.globalX = temp.positionInScreen().x;
+  result.globalY = temp.positionInScreen().y;
 
   result.setModifiers(ModifiersFromEvent(event));
   result.setTimeStampSeconds([event timestamp]);
 
   result.sourceDevice = blink::WebGestureDeviceTouchpad;
   switch ([event type]) {
     case NSEventTypeMagnify:
       result.setType(blink::WebInputEvent::GesturePinchUpdate);
       result.data.pinchUpdate.scale = [event magnification] + 1.0;
       break;
@@ skipping 12 matching lines @@
       // to specify them when the gesture is differentiated.
       break;
     default:
       NOTIMPLEMENTED();
   }
 
   return result;
 }
 
 }  // namespace content