Modify iOSShell-gyp to generate unique bundle identifier

gyp/iOSShell.gyp

   # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 {
   'conditions' : [
     [ 'skia_os == "ios"', {
       'targets': [
         {
@@ skipping 50 matching lines @@
           },
           'include_dirs' : [
             '../experimental/iOSSampleApp',
             '../experimental/iOSSampleApp/iPad',
             '../experimental/iOSSampleApp/iPhone',
             '../experimental/iOSSampleApp/Shared',
             '../include/utils/ios',
             '../src/views/mac',
           ],
           'xcode_settings' : {
+            'PRODUCT_BUNDLE_IDENTIFIER' : '<!(echo com.google.iOSShell.`hostname | md5`)',
             'INFOPLIST_FILE' : '../experimental/iOSShell/iOSShell-Info.plist',
           },
           'xcode_config_file': '../experimental/iOSSampleApp/SkiOSSampleApp-Base.xcconfig',
           'mac_bundle_resources' : [
             '../experimental/iOSSampleApp/iPad/MainWindow_iPad.xib',
             '../experimental/iOSSampleApp/iPhone/MainWindow_iPhone.xib',
           ],
           'conditions' : [
             [ 'skia_gpu == 1', {
               'dependencies': [
                 'gputest.gyp:skgputest',
               ],
             }],
           ],
         },
       ],
     }],
   ]
 }