Revert of Add support for glMapBufferRange. Use glMapBufferRange and glMapBufferSubData.

src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp

Index: src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp
diff --git a/src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp b/src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp
index cb2fc953365ed98fe6634aebe25eec67596bbc4a..a316ff1c11913c6c8eb82822e9535577019f213b 100644
--- a/src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp
+++ b/src/gpu/gl/angle/GrGLCreateANGLEInterface.cpp
@@ -154,14 +154,6 @@
     functions->fMapBuffer = (GrGLMapBufferProc) eglGetProcAddress("glMapBufferOES");
     functions->fUnmapBuffer = (GrGLUnmapBufferProc) eglGetProcAddress("glUnmapBufferOES");
 
-#if GL_ES_VERSION_3_0
-    functions->fMapBufferRange = GET_PROC(glMapBufferRange);
-    functions->fFlushMappedBufferRange = GET_PROC(glFlushMappedBufferRange);
-#else
-    functions->fMapBufferRange = (GrGLMapBufferRangeProc) eglGetProcAddress("glMapBufferRange");
-    functions->fFlushMappedBufferRange = (GrGLFlushMappedBufferRangeProc) eglGetProcAddress("glFlushMappedBufferRange");
-#endif
-
     functions->fInsertEventMarker = (GrGLInsertEventMarkerProc) eglGetProcAddress("glInsertEventMarkerEXT");
     functions->fPushGroupMarker = (GrGLInsertEventMarkerProc) eglGetProcAddress("glPushGroupMarkerEXT");
     functions->fPopGroupMarker = (GrGLPopGroupMarkerProc) eglGetProcAddress("glPopGroupMarkerEXT");