MacViews: Fix sending mouse exit event and releasing capture on D&D.

ui/views/cocoa/bridged_content_view.mm

 // 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 "ui/views/cocoa/bridged_content_view.h"
 
 #include "base/logging.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 537 matching lines @@
 
   ui::MouseEvent event(theEvent);
 
   // Aura updates tooltips with the help of aura::Window::AddPreTargetHandler().
   // Mac hooks in here.
   [self updateTooltipIfRequiredAt:event.location()];
 
   hostedView_->GetWidget()->OnMouseEvent(&event);
 }
 
+// http://crbug.com/646792
+// Disable pendingExitEvent_ logic in BaseView.
+- (void)mouseDown:(NSEvent*)theEvent {

[snake, 2016/09/22 18:22:39]

What about this MacViews specific fix, for now?

[tapted, 2016/09/23 07:10:21]

The code looks good, but I tried commenting this out and can't tell the
difference in behaviour. You explained earlier that the MouseExit could be
ignored - I tried dragging from the bookmarks bar and showing menus, but it
seems to work fine without this. I'm probably missing something.

As well as saying what the override is doing (as you have), can you explain in
the comment why it's necessary? There was a chromium-dev post about this
recently -- see
https://groups.google.com/a/chromium.org/d/msg/chromium-dev/MY4e_wJY6yY/cOVLt...

The CL description needs to be updated too.

[snake, 2016/09/26 10:28:48]

hm.. I will investigate this. I did remove this for now.

Done.

+  [self mouseEvent:theEvent];
+}
+
 // NSView implementation.
 
 - (BOOL)acceptsFirstResponder {
   return YES;
 }
 
 - (BOOL)becomeFirstResponder {
   BOOL result = [super becomeFirstResponder];
   if (result && hostedView_)
     hostedView_->GetWidget()->GetFocusManager()->RestoreFocusedView();
@@ skipping 788 matching lines @@
   }
 
   return [super accessibilityAttributeValue:attribute];
 }
 
 - (id)accessibilityHitTest:(NSPoint)point {
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
 @end