Add NSString category for providing iOS6-style string drawing APIs.

ui/ios/ui_ios.gyp

 # Copyright 2014 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
-      'target_name': 'device_core',
+      'target_name': 'ui_ios',
       'type': 'static_library',
+      # Linkable dependents need to set the linker flag '-ObjC' in order to use
+      # the categories in this target (e.g. NSString+CrStringDrawing.h).
+      'link_settings': {
+        'xcode_settings': {'OTHER_LDFLAGS': ['-ObjC']},
+      },
       'include_dirs': [
         '../..',
       ],
       'sources': [
-        'device_client.cc',
-        'device_client.h',
+        'NSString+CrStringDrawing.h',
+        'NSString+CrStringDrawing.mm',
       ],
     },
   ],
 }