Now able to set Chrome as the default browser on Mac.

chrome/browser/shell_integration_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/shell_integration.h"
 
 #include "base/mac/bundle_locations.h"
 #include "base/mac/foundation_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/common/channel_info.h"
@@ skipping 35 matching lines @@
       [default_client caseInsensitiveCompare:identifier];
   return result == NSOrderedSame;
 }
 
 }  // namespace
 
 // Sets Chromium as default browser to be used by the operating system. This
 // applies only for the current user. Returns false if this cannot be done, or
 // if the operation fails.
 bool SetAsDefaultBrowser() {
-  if (CanSetAsDefaultBrowser())
+  if (!CanSetAsDefaultBrowser())
     return false;
 
   // We really do want the outer bundle here, not the main bundle since setting
   // a shortcut to Chrome as the default browser doesn't make sense.
   NSString* identifier = [base::mac::OuterBundle() bundleIdentifier];
   if (!identifier)
     return false;
 
   [[NSWorkspace sharedWorkspace] setDefaultBrowserWithIdentifier:identifier];
   return true;
@@ skipping 79 matching lines @@
   NSString* my_identifier = [base::mac::MainBundle() bundleIdentifier];
   if (!my_identifier)
     return UNKNOWN_DEFAULT;
 
   NSString* protocol_ns = [NSString stringWithUTF8String:protocol.c_str()];
   return IsIdentifierDefaultProtocolClient(my_identifier, protocol_ns) ?
       IS_DEFAULT : NOT_DEFAULT;
 }
 
 }  // namespace shell_integration