mac: Tentative fix for Yosemite open file crash.

chrome/browser/chrome_browser_main_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.
 
 #include "chrome/browser/chrome_browser_main_mac.h"
 
 #import <Cocoa/Cocoa.h>
 #include <sys/sysctl.h>
 
 #include "base/command_line.h"
@@ skipping 241 matching lines @@
       // Prevent Cocoa from turning command-line arguments into
       // |-application:openFiles:|, since we already handle them directly.
       // @"NO" looks like a mistake, but the value really is supposed to be a
       // string.
       @"NSTreatUnknownArgumentsAsOpen": @"NO",
       // CoreAnimation has poor performance and CoreAnimation and
       // non-CoreAnimation exhibit window flickering when layers are not hosted
       // in the window server, which is the default when not not using the
       // 10.9 SDK.
       // TODO: Remove this when we build with the 10.9 SDK.
-      @"NSWindowHostsLayersInWindowServer": @(base::mac::IsOSMavericksOrLater())
+      @"NSWindowHostsLayersInWindowServer":
+          @(base::mac::IsOSMavericksOrLater()),
+      // This setting prevents views from ditching their layers when the view
+      // gets removed from the view hierarchy. It defaults to YES for
+      // applications linked against an OSX 10.8+ SDK. In Yosemite, failing to
+      // set this to YES causes an AppKit crash. http://crbug.com/428977
+      // TODO(erikchen): Remove this when we build with an OSX 10.8+ SDK.
+      @"NSViewKeepLayersAround": @(YES)
   }];
 }
 
 void ChromeBrowserMainPartsMac::PostMainMessageLoopStart() {
   MacStartupProfiler::GetInstance()->Profile(
       MacStartupProfiler::POST_MAIN_MESSAGE_LOOP_START);
   ChromeBrowserMainPartsPosix::PostMainMessageLoopStart();
 }
 
 void ChromeBrowserMainPartsMac::PreProfileInit() {
@@ skipping 13 matching lines @@
       MacStartupProfiler::POST_PROFILE_INIT);
   ChromeBrowserMainPartsPosix::PostProfileInit();
   g_browser_process->metrics_service()->RecordBreakpadRegistration(
       breakpad::IsCrashReporterEnabled());
 }
 
 void ChromeBrowserMainPartsMac::DidEndMainMessageLoop() {
   AppController* appController = [NSApp delegate];
   [appController didEndMainMessageLoop];
 }