Disable window occlusion APIs when running browser tests

content/browser/web_contents/web_contents_view_mac.mm

 // 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.
 
 #import <Carbon/Carbon.h>
 
 #import "content/browser/web_contents/web_contents_view_mac.h"
 
 #include <string>
 
+#include "base/command_line.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_sending_event.h"
 #include "base/mac/sdk_forward_declarations.h"
 #include "base/message_loop/message_loop.h"
 #import "base/message_loop/message_pump_mac.h"
 #include "content/browser/frame_host/popup_menu_helper_mac.h"
 #include "content/browser/renderer_host/render_view_host_factory.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #import "content/browser/web_contents/web_drag_dest_mac.h"
 #import "content/browser/web_contents/web_drag_source_mac.h"
 #include "content/common/view_messages.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_view_delegate.h"
+#include "content/public/common/content_switches.h"
 #include "skia/ext/skia_utils_mac.h"
 #import "third_party/mozilla/NSPasteboard+Utils.h"
 #include "ui/base/clipboard/custom_data_helper.h"
 #import "ui/base/cocoa/focus_tracker.h"
 #include "ui/base/dragdrop/cocoa_dnd_util.h"
 #include "ui/gfx/image/image_skia_util_mac.h"
 
 using blink::WebDragOperation;
 using blink::WebDragOperationsMask;
 using content::DropData;
@@ skipping 593 matching lines @@
   for (NSView* subview in self.subviews)
     [subview setFrame:self.bounds];
 }
 
 - (void)viewWillMoveToWindow:(NSWindow*)newWindow {
   NSWindow* oldWindow = [self window];
 
   NSNotificationCenter* notificationCenter =
       [NSNotificationCenter defaultCenter];
 
-  // Occlusion notification APIs are new in Mavericks.
-  bool supportsOcclusionAPIs = base::mac::IsOSMavericksOrLater();
+  // Occlusion is highly undesirable for browser tests, since it will
+  // flakily change behavior.

[Noel Gordon, 2016/03/04 01:57:32]

"change" - > "change test" ?

[ccameron, 2016/03/06 23:09:08]

Done.

+  static bool isDisabled = base::CommandLine::ForCurrentProcess()->HasSwitch(

[Noel Gordon, 2016/03/04 01:57:32]

Is using a static safe for all test scenarios?

[ccameron, 2016/03/06 23:09:08]

I tested single and multi-process and both worked. I've also added the
"ForTesting" suffix to ensure that people don't think this is a good idea
outside of tests.

+      switches::kDisableBackgroundingOccludedWindows);
 
-  if (supportsOcclusionAPIs) {
+  if (!isDisabled) {
     if (oldWindow) {
       [notificationCenter
           removeObserver:self
                     name:NSWindowDidChangeOcclusionStateNotification
                   object:oldWindow];
     }
     if (newWindow) {
       [notificationCenter
           addObserver:self
              selector:@selector(windowChangedOcclusionState:)
@@ skipping 22 matching lines @@
 
 - (void)viewDidHide {
   [self updateWebContentsVisibility];
 }
 
 - (void)viewDidUnhide {
   [self updateWebContentsVisibility];
 }
 
 @end