implement getBufferSubDataAsync prototype

gpu/command_buffer/client/gles2_c_lib_autogen.h

Index: gpu/command_buffer/client/gles2_c_lib_autogen.h
diff --git a/gpu/command_buffer/client/gles2_c_lib_autogen.h b/gpu/command_buffer/client/gles2_c_lib_autogen.h
index a3e11c64805ec86969daeebd2ca819b8cd57c7a6..2c180c00524b70877bdd0bb23a838c82c9ec8eb4 100644
--- a/gpu/command_buffer/client/gles2_c_lib_autogen.h
+++ b/gpu/command_buffer/client/gles2_c_lib_autogen.h
@@ -1664,6 +1664,12 @@ GLES2ProgramPathFragmentInputGenCHROMIUM(GLuint program,
   gles2::GetGLContext()->ProgramPathFragmentInputGenCHROMIUM(
       program, location, genMode, components, coeffs);
 }
+void* GL_APIENTRY GLES2GetBufferSubDataAsyncCHROMIUM(GLenum target,
+                                                     GLintptr offset,
+                                                     GLsizeiptr size) {
+  return gles2::GetGLContext()->GetBufferSubDataAsyncCHROMIUM(target, offset,
+                                                              size);
+}
 void GL_APIENTRY GLES2CoverageModulationCHROMIUM(GLenum components) {
   gles2::GetGLContext()->CoverageModulationCHROMIUM(components);
 }
@@ -2961,6 +2967,10 @@ extern const NameToFunc g_gles2_function_table[] = {
             glProgramPathFragmentInputGenCHROMIUM),
     },
     {
+        "glGetBufferSubDataAsyncCHROMIUM",
+        reinterpret_cast<GLES2FunctionPointer>(glGetBufferSubDataAsyncCHROMIUM),
+    },
+    {
         "glCoverageModulationCHROMIUM",
         reinterpret_cast<GLES2FunctionPointer>(glCoverageModulationCHROMIUM),
     },