Add EncodeBackbufferCHROMIUM support to GLES2 command stream

gpu/command_buffer/build_gles2_cmd_buffer.py

 #!/usr/bin/env python
 # 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.
 
 """code generator for GLES2 command buffers."""
 
 import itertools
 import os
 import os.path
@@ skipping 2338 matching lines @@
     'impl_func': False,
     'extension': True,
     'chromium': True,
   },
   'WaitSyncPointCHROMIUM': {
     'type': 'Custom',
     'impl_func': True,
     'extension': True,
     'chromium': True,
   },
+  'EncodeBackbufferCHROMIUM': {
+    'type': 'Custom',
+    'impl_func': True,
+    'extension': True,
+    'chromium': True,
+  },
 }
 
 
 def Grouper(n, iterable, fillvalue=None):
   """Collect data into fixed-length chunks or blocks"""
   args = [iter(iterable)] * n
   return itertools.izip_longest(fillvalue=fillvalue, *args)
 
 
 def SplitWords(input_string):
@@ skipping 5292 matching lines @@
     gen.WriteGLES2Header("../GLES2/gl2chromium_autogen.h")
 
   if gen.errors > 0:
     print "%d errors" % gen.errors
     return 1
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))