Fix analyzer errors in html Dartium.

sdk/lib/_blink/dartium/_blink_dartium.dart

 /**
  * This library provides entry points to the native Blink code which backs
  * up the dart:html library.
  */
 library dart.dom._blink;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:html';
 import 'dart:_internal' hide Symbol, deprecated;
@@ skipping 7185 matching lines @@
 
 Native_TreeWalker_previousNode_Callback(mthis) native "TreeWalker_previousNode_Callback";
 
 Native_TreeWalker_previousSibling_Callback(mthis) native "TreeWalker_previousSibling_Callback";
 
   // Generated overload resolver
 Native_URL_createObjectUrl(blob_OR_source_OR_stream) {
     if ((blob_OR_source_OR_stream is Blob || blob_OR_source_OR_stream == null)) {
       return Native_URL__createObjectURL_1_Callback(blob_OR_source_OR_stream);
     }
-    if ((blob_OR_source_OR_stream is MediaStream || blob_OR_source_OR_stream == null)) {
+    if ((blob_OR_source_OR_stream is MediaSource || blob_OR_source_OR_stream == null)) {

[Leaf, 2014/05/14 21:42:09]

I don't understand why these lines changed, base on the rest of the patch.  This
file is generated, and I don't see any corresponding changes that should cause
this to change - am I missing something?

[Emily Fortuna, 2014/05/14 21:49:53]

Yep, this actually changes if you run go.sh on a clean checkout, so it's not
from this change. I'll take it out of this CL, but it will go in eventually....

       return Native_URL__createObjectURL_2_Callback(blob_OR_source_OR_stream);
     }
-    if ((blob_OR_source_OR_stream is MediaSource || blob_OR_source_OR_stream == null)) {
+    if ((blob_OR_source_OR_stream is MediaStream || blob_OR_source_OR_stream == null)) {
       return Native_URL__createObjectURL_3_Callback(blob_OR_source_OR_stream);
     }
     throw new ArgumentError("Incorrect number or type of arguments");
   }
 
 Native_URL__createObjectURL_1_Callback(blob_OR_source_OR_stream) native "URL__createObjectURL_1_Callback";
 
 Native_URL__createObjectURL_2_Callback(blob_OR_source_OR_stream) native "URL__createObjectURL_2_Callback";
 
 Native_URL__createObjectURL_3_Callback(blob_OR_source_OR_stream) native "URL__createObjectURL_3_Callback";
@@ skipping 1130 matching lines @@
 // _DOMStringMap native entry  points
 Native_DOMStringMap_containsKey(_DOMStringMap, key) native "DOMStringMap_containsKey_Callback";
 
 Native_DOMStringMap_item(_DOMStringMap, key) native "DOMStringMap_item_Callback";
 
 Native_DOMStringMap_setItem(_DOMStringMap, key, value) native "DOMStringMap_setItem_Callback";
 
 Native_DOMStringMap_remove(_DOMStringMap, key) native "DOMStringMap_remove_Callback";
 
 Native_DOMStringMap_get_keys(_DOMStringMap) native "DOMStringMap_getKeys_Callback";