Add GL_EXT_multisampled_render_to_texture support to 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 c4143715cedee482b5745a94e088d75de1dfde50..f7b9a5b74b5a261f8397bcdf214617497a413f1b 100644
--- a/gpu/command_buffer/cmd_buffer_functions.txt
+++ b/gpu/command_buffer/cmd_buffer_functions.txt
@@ -150,6 +150,7 @@ GL_APICALL void         GL_APIENTRY glVertexAttribPointer (GLuint indx, GLintVer
 GL_APICALL void         GL_APIENTRY glViewport (GLint x, GLint y, GLsizei width, GLsizei height);
 GL_APICALL void         GL_APIENTRY glBlitFramebufferEXT (GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1, GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1, GLbitfield mask, GLenumBlitFilter filter);
 GL_APICALL void         GL_APIENTRY glRenderbufferStorageMultisampleEXT (GLenumRenderBufferTarget target, GLsizei samples, GLenumRenderBufferFormat internalformat, GLsizei width, GLsizei height);
+GL_APICALL void         GL_APIENTRY glFramebufferTexture2DMultisampleEXT (GLenumFrameBufferTarget target, GLenumAttachment attachment, GLenumTextureTarget textarget, GLidTexture texture, GLintZeroOnly level, GLsizei samples);
 GL_APICALL void         GL_APIENTRY glTexStorage2DEXT (GLenumTextureTarget target, GLsizei levels, GLenumTextureInternalFormatStorage internalFormat, GLsizei width, GLsizei height);
 GL_APICALL void         GL_APIENTRY glGenQueriesEXT (GLsizeiNotNegative n, GLuint* queries);
 GL_APICALL void         GL_APIENTRY glDeleteQueriesEXT (GLsizeiNotNegative n, const GLuint* queries);