Fix Try Dart newline handling on IE11.

sdk/lib/html/dartium/html_dartium.dart

Index: sdk/lib/html/dartium/html_dartium.dart
===================================================================
--- sdk/lib/html/dartium/html_dartium.dart	(revision 39571)
+++ sdk/lib/html/dartium/html_dartium.dart	(working copy)
@@ -10413,7 +10413,7 @@
    * Adds the specified text after the last child of this element.
    */
   void appendText(String text) {
-    this.insertAdjacentText('beforeend', text);
+    this.append(new Text(text));
   }
 
   /**
@@ -28752,10 +28752,10 @@
     if ((blob_OR_source_OR_stream is Blob || blob_OR_source_OR_stream == null)) {
       return _blink.BlinkURL.$_createObjectURL_1_Callback(blob_OR_source_OR_stream);
     }
-    if ((blob_OR_source_OR_stream is MediaStream || blob_OR_source_OR_stream == null)) {
+    if ((blob_OR_source_OR_stream is MediaSource || blob_OR_source_OR_stream == null)) {
       return _blink.BlinkURL.$_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 _blink.BlinkURL.$_createObjectURL_3_Callback(blob_OR_source_OR_stream);
     }
     throw new ArgumentError("Incorrect number or type of arguments");