Rename dart:typeddata to dart:typed_data.

runtime/lib/typed_data_sources.gypi

Index: runtime/lib/typed_data_sources.gypi
diff --git a/runtime/lib/typeddata_sources.gypi b/runtime/lib/typed_data_sources.gypi
similarity index 73%
rename from runtime/lib/typeddata_sources.gypi
rename to runtime/lib/typed_data_sources.gypi
index fc5ba11b08aad6eb09e452466e314dcaa99f03b5..28d6a53e538714fbc8d44bc50d85479eaf9c043b 100644
--- a/runtime/lib/typeddata_sources.gypi
+++ b/runtime/lib/typed_data_sources.gypi
@@ -2,12 +2,12 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
-# Sources visible via dart:typeddata library.
+# Sources visible via dart:typed_data library.
 
 {
   'sources': [
-    'typeddata.cc',
-    'typeddata.dart',
+    'typed_data.cc',
+    'typed_data.dart',
     'simd128.cc',
   ],
 }