Give CodeEmitterTask a name for -v compiles

pkg/compiler/lib/src/js_emitter/code_emitter_task.dart

Index: pkg/compiler/lib/src/js_emitter/code_emitter_task.dart
diff --git a/pkg/compiler/lib/src/js_emitter/code_emitter_task.dart b/pkg/compiler/lib/src/js_emitter/code_emitter_task.dart
index 1ed955de6b8697b24c611d8392df2f5cdc6dd14d..ca84c03a141a9c7a0e682a7e0bea3c7b7571943a 100644
--- a/pkg/compiler/lib/src/js_emitter/code_emitter_task.dart
+++ b/pkg/compiler/lib/src/js_emitter/code_emitter_task.dart
@@ -58,6 +58,8 @@ class CodeEmitterTask extends CompilerTask {
     nativeEmitter = new NativeEmitter(this);
   }
 
+  String get name => 'Code emitter';
+
   /// Returns the closure expression of a static function.
   jsAst.Expression isolateStaticClosureAccess(FunctionElement element) {
     return emitter.isolateStaticClosureAccess(element);