Add GL_CHROMIUM_screen_space_antialiasing to support alternative AA

gpu/command_buffer/common/gles2_cmd_ids_autogen.h

 // 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.
 
 // This file is auto-generated from
 // gpu/command_buffer/build_gles2_cmd_buffer.py
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 298 matching lines @@
   OP(PathCommandsCHROMIUM)                     /* 550 */ \
   OP(PathParameterfCHROMIUM)                   /* 551 */ \
   OP(PathParameteriCHROMIUM)                   /* 552 */ \
   OP(PathStencilFuncCHROMIUM)                  /* 553 */ \
   OP(StencilFillPathCHROMIUM)                  /* 554 */ \
   OP(StencilStrokePathCHROMIUM)                /* 555 */ \
   OP(CoverFillPathCHROMIUM)                    /* 556 */ \
   OP(CoverStrokePathCHROMIUM)                  /* 557 */ \
   OP(StencilThenCoverFillPathCHROMIUM)         /* 558 */ \
   OP(StencilThenCoverStrokePathCHROMIUM)       /* 559 */ \
-  OP(BlendBarrierKHR)                          /* 560 */
+  OP(BlendBarrierKHR)                          /* 560 */ \
+  OP(ApplyScreenSpaceAntialiasingCHROMIUM)     /* 561 */
 
 enum CommandId {
   kStartPoint = cmd::kLastCommonId,  // All GLES2 commands start after this.
 #define GLES2_CMD_OP(name) k##name,
   GLES2_COMMAND_LIST(GLES2_CMD_OP)
 #undef GLES2_CMD_OP
       kNumCommands
 };
 
 #endif  // GPU_COMMAND_BUFFER_COMMON_GLES2_CMD_IDS_AUTOGEN_H_