Deprecate new internal Dartium/JsInterop APIs that are public

tools/dom/templates/html/dartium/web_gl_dartium.darttemplate

 // DO NOT EDIT
 // Auto-generated dart:web_gl library.
 
 /**
  * 3D programming in the browser.
  */
 library dart.dom.web_gl;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:_internal';
 import 'dart:html';
 import 'dart:html_common';
 import 'dart:nativewrappers';
 import 'dart:typed_data';
 import 'dart:_blink' as _blink;
 import 'dart:js' as js;
 
 part '$AUXILIARY_DIR/WebGLConstants.dart';
 
 $!GENERATED_DART_FILES
 // FIXME: Can we make this private?
+@Deprecated("Internal Use Only")
 final web_glBlinkMap = {
 $!TYPE_MAP
 };
 
 $if JSINTEROP
 // FIXME: Can we make this private?
+@Deprecated("Internal Use Only")
 final web_glBlinkFunctionMap = {
 $!TYPE_FUNCTION_MAP
 };
 $endif