[Mac] Implement NSObject zombies.

chrome/browser/chrome_browser_application_mac.mm

 // Copyright (c) 2010 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 "chrome/browser/chrome_browser_application_mac.h"
 
 #import "base/histogram.h"
 #import "base/logging.h"
 #import "base/scoped_nsobject.h"
 #import "base/sys_string_conversions.h"
 #import "chrome/app/breakpad_mac.h"
 #import "chrome/browser/app_controller_mac.h"
 #import "chrome/browser/cocoa/objc_method_swizzle.h"
+#import "chrome/browser/cocoa/objc_zombie.h"
 
 // The implementation of NSExceptions break various assumptions in the
 // Chrome code.  This category defines a replacement for
 // -initWithName:reason:userInfo: for purposes of forcing a break in
 // the debugger when an exception is raised.  -raise sounds more
 // obvious to intercept, but it doesn't catch the original throw
 // because the objc runtime doesn't use it.
 @interface NSException (NSExceptionSwizzle)
 - (id)chromeInitWithName:(NSString *)aName
                   reason:(NSString *)aReason
@@ skipping 130 matching lines @@
       [NSException class],
       @selector(initWithName:reason:userInfo:),
       @selector(chromeInitWithName:reason:userInfo:));
   return YES;
 }
 
 }  // namespace
 
 @implementation BrowserCrApplication
 
++ (void)initialize {
+  // Turn all deallocated Objective-C objects into zombies, keeping
+  // the most recent 10,000 of them on the treadmill.
+  DCHECK(ObjcEvilDoers::ZombieEnable(YES, 10000));
+}
+
 - init {
   DCHECK(SwizzleNSExceptionInit());
   return [super init];
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // HISTORICAL COMMENT (by viettrungluu, from
 // http://codereview.chromium.org/1520006 with mild editing):
 //
 // A quick summary of the state of things (before the changes to shutdown):
@@ skipping 157 matching lines @@
       SetCrashKeyValue(kLastExceptionKey, value);
     }
 
     reportingException = NO;
   }
 
   [super reportException:anException];
 }
 
 @end