Add "create_bundle" target in order to support bundle with gn.

tools/gn/functions.cc

 // Copyright (c) 2013 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 "tools/gn/functions.h"
 
 #include <stddef.h>
 #include <iostream>
 #include <utility>
 
@@ skipping 786 matching lines @@
   FunctionInfoInitializer() {
     #define INSERT_FUNCTION(command, is_target) \
         map[k##command] = FunctionInfo(&Run##command, \
                                        k##command##_HelpShort, \
                                        k##command##_Help, \
                                        is_target);
 
     INSERT_FUNCTION(Action, true)
     INSERT_FUNCTION(ActionForEach, true)
     INSERT_FUNCTION(BundleData, true)
+    INSERT_FUNCTION(CreateBundle, true)
     INSERT_FUNCTION(Copy, true)
     INSERT_FUNCTION(Executable, true)
     INSERT_FUNCTION(Group, true)
     INSERT_FUNCTION(LoadableModule, true)
     INSERT_FUNCTION(SharedLibrary, true)
     INSERT_FUNCTION(SourceSet, true)
     INSERT_FUNCTION(StaticLibrary, true)
     INSERT_FUNCTION(Target, true)
 
     INSERT_FUNCTION(Assert, false)
@@ skipping 103 matching lines @@
   }
 
   // Otherwise it's a no-block function.
   if (!VerifyNoBlockForFunctionCall(function, block, err))
     return Value();
   return found_function->second.no_block_runner(scope, function,
                                                 args.list_value(), err);
 }
 
 }  // namespace functions