Implementing FlushMappedBufferRange in GPU command buffer.

gpu/command_buffer/cmd_buffer_functions.txt

Index: gpu/command_buffer/cmd_buffer_functions.txt
diff --git a/gpu/command_buffer/cmd_buffer_functions.txt b/gpu/command_buffer/cmd_buffer_functions.txt
index 3b6348041a86d5d75b9e70c9be3322dc83ca8672..1da56a73a88ff64e15f9de9e049a9963f0df0748 100644
--- a/gpu/command_buffer/cmd_buffer_functions.txt
+++ b/gpu/command_buffer/cmd_buffer_functions.txt
@@ -264,6 +264,7 @@ GL_APICALL void*        GL_APIENTRY glMapBufferSubDataCHROMIUM (GLuint target, G
 GL_APICALL void         GL_APIENTRY glUnmapBufferSubDataCHROMIUM (const void* mem);
 GL_APICALL void*        GL_APIENTRY glMapBufferRange (GLenumBufferTarget target, GLintptrNotNegative offset, GLsizeiptr size, GLbitfieldMapBufferAccess access);
 GL_APICALL GLboolean    GL_APIENTRY glUnmapBuffer (GLenumBufferTarget target);
+GL_APICALL void         GL_APIENTRY glFlushMappedBufferRange (GLenumBufferTarget target, GLintptrNotNegative offset, GLsizeiptr size);
 GL_APICALL void*        GL_APIENTRY glMapTexSubImage2DCHROMIUM (GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, GLenum access);
 GL_APICALL void         GL_APIENTRY glUnmapTexSubImage2DCHROMIUM (const void* mem);
 GL_APICALL void         GL_APIENTRY glResizeCHROMIUM (GLuint width, GLuint height, GLfloat scale_factor, GLboolean alpha);