[Mac] Remove usage of deprecated Carbon SetFrontProcessWithOptions().

Replace with -[NSRunningApplication activateWithOptions:].

BUG=650845
R=avi@chromium.org

Review-Url: https://codereview.chromium.org/2386343004
Cr-Commit-Position: refs/heads/master@{#422973}

chrome/browser/ui/cocoa/browser_window_utils.mm

@@ -4,8 +4,6 @@
 
 #import "chrome/browser/ui/cocoa/browser_window_utils.h"
 
-#include <Carbon/Carbon.h>
-
 #include "base/logging.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/global_keyboard_shortcuts_mac.h"
@@ -149,9 +147,7 @@ const CGFloat kPatternHorizontalOffset = -5;
   // Per http://crbug.com/73779 and http://crbug.com/75223, we need this to
   // properly activate windows if Chrome is not the active application.
   [[controller window] makeKeyAndOrderFront:controller];
-  ProcessSerialNumber psn;
-  GetCurrentProcess(&psn);
-  SetFrontProcessWithOptions(&psn, kSetFrontProcessFrontWindowOnly);
+  [[NSRunningApplication currentApplication] activateWithOptions:0];
 }
 
 @end