[turbofan] Support fast access to the current global object.

src/v8.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 614 matching lines @@
         'compiler/js-call-reducer.cc',
         'compiler/js-call-reducer.h',
         'compiler/js-context-specialization.cc',
         'compiler/js-context-specialization.h',
         'compiler/js-create-lowering.cc',
         'compiler/js-create-lowering.h',
         'compiler/js-frame-specialization.cc',
         'compiler/js-frame-specialization.h',
         'compiler/js-generic-lowering.cc',
         'compiler/js-generic-lowering.h',
-        'compiler/js-global-object-specialization.cc',
-        'compiler/js-global-object-specialization.h',
         'compiler/js-graph.cc',
         'compiler/js-graph.h',
         'compiler/js-inlining.cc',
         'compiler/js-inlining.h',
         'compiler/js-inlining-heuristic.cc',
         'compiler/js-inlining-heuristic.h',
         'compiler/js-intrinsic-lowering.cc',
         'compiler/js-intrinsic-lowering.h',
         'compiler/js-native-context-specialization.cc',
         'compiler/js-native-context-specialization.h',
@@ skipping 1855 matching lines @@
       'conditions': [
         ['want_separate_host_toolset_mkpeephole==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }