Add ScopedObjCClassSwizzler in base/mac, absorbs objc_method_swizzle and ScopedClassSwizzler

chrome/browser/chrome_browser_application_mac.mm

Index: chrome/browser/chrome_browser_application_mac.mm
diff --git a/chrome/browser/chrome_browser_application_mac.mm b/chrome/browser/chrome_browser_application_mac.mm
index 3368c06351486e4ff3bf4657a30be1c00d1b420f..af0b6e663b971d5ffc4f0ed5a9e3bfbea5c68175 100644
--- a/chrome/browser/chrome_browser_application_mac.mm
+++ b/chrome/browser/chrome_browser_application_mac.mm
@@ -10,13 +10,13 @@
 #import "base/logging.h"
 #import "base/mac/scoped_nsexception_enabler.h"
 #import "base/mac/scoped_nsobject.h"
+#import "base/mac/scoped_objc_class_swizzler.h"
 #import "base/metrics/histogram.h"
 #include "base/strings/stringprintf.h"
 #import "base/strings/sys_string_conversions.h"
 #import "chrome/browser/app_controller_mac.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_iterator.h"
 #include "chrome/common/crash_keys.h"
-#import "chrome/common/mac/objc_method_swizzle.h"
 #import "chrome/common/mac/objc_zombie.h"
 #include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/browser/render_view_host.h"
@@ -24,7 +24,7 @@
 
 namespace {
 
-// Tracking for cases being hit by -crInitWithName:reason:userInfo:.
+// Tracking for cases being hit by -initWithName:reason:userInfo:.
 enum ExceptionEventType {
   EXCEPTION_ACCESSIBILITY = 0,
   EXCEPTION_MENU_ITEM_BOUNDS_CHECK,
@@ -44,25 +44,25 @@ void RecordExceptionEvent(ExceptionEventType event_type) {
 }  // namespace
 
 // The implementation of NSExceptions break various assumptions in the
-// Chrome code.  This category defines a replacement for
+// Chrome code.  This interface 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 (CrNSExceptionSwizzle)
-- (id)crInitWithName:(NSString*)aName
-              reason:(NSString*)aReason
-            userInfo:(NSDictionary*)someUserInfo;
+@interface CrNSExceptionInitDonor : NSObject
+- (id)initWithName:(NSString*)aName
+            reason:(NSString*)aReason
+          userInfo:(NSDictionary*)someUserInfo;
 @end
 
 static IMP gOriginalInitIMP = NULL;
 
-@implementation NSException (CrNSExceptionSwizzle)
-- (id)crInitWithName:(NSString*)aName
-              reason:(NSString*)aReason
-            userInfo:(NSDictionary*)someUserInfo {
+@implementation CrNSExceptionInitDonor
+- (id)initWithName:(NSString*)aName
+            reason:(NSString*)aReason
+          userInfo:(NSDictionary*)someUserInfo {
   // Method only called when swizzled.
-  DCHECK(_cmd == @selector(initWithName:reason:userInfo:));
+  DCHECK(gOriginalInitIMP);
 
   // Parts of Cocoa rely on creating and throwing exceptions. These are not
   // worth bugging-out over. It is very important that there be zero chance that
@@ -235,10 +235,12 @@ void SwizzleInit() {
   // Do-nothing wrapper so that we can arrange to only swizzle
   // -[NSException raise] when DCHECK() is turned on (as opposed to
   // replicating the preprocess logic which turns DCHECK() on).
-  gOriginalInitIMP = ObjcEvilDoers::SwizzleImplementedInstanceMethods(
-      [NSException class],
-      @selector(initWithName:reason:userInfo:),
-      @selector(crInitWithName:reason:userInfo:));
+  CR_DEFINE_STATIC_LOCAL(base::mac::ScopedObjCClassSwizzler,
+                         swizzle_exception,
+                         ([NSException class],
+                          [CrNSExceptionInitDonor class],
+                          @selector(initWithName:reason:userInfo:)));
+  gOriginalInitIMP = swizzle_exception.GetOriginalImplementation();
 }
 
 }  // namespace