Optimize StackTrace.current Eliminate redundant call to captureStackTrace and compute the stack tra…

sdk/lib/convert/line_splitter.dart

Index: sdk/lib/convert/line_splitter.dart
diff --git a/sdk/lib/convert/line_splitter.dart b/sdk/lib/convert/line_splitter.dart
index 4e3778de08a426093d8c7008e45df37b7509f49a..9fd3d5eac15506783303cbc0c272b19736c4b3f2 100644
--- a/sdk/lib/convert/line_splitter.dart
+++ b/sdk/lib/convert/line_splitter.dart
@@ -19,9 +19,7 @@ const int _CR = 13;
  */
 
 class LineSplitter
-    extends Converter<String, List<String>>/*=Object*/
-    implements ChunkedConverter<String, List<String>, String, String>
-        /*=StreamTransformer<String, String>*/ {
+    implements StreamTransformer<String, String> {
 
   const LineSplitter();
 
@@ -84,7 +82,7 @@ class LineSplitter
     return new _LineSplitterSink(sink);
   }
 
-  Stream/*<String>*/ bind(Stream<String> stream) {
+  Stream<String> bind(Stream<String> stream) {
     return new Stream<String>.eventTransformed(
           stream,
           (EventSink<String> sink) => new _LineSplitterEventSink(sink));