Better hints for await in non-async functions

pkg/compiler/lib/src/resolution/members.dart

Index: pkg/compiler/lib/src/resolution/members.dart
diff --git a/pkg/compiler/lib/src/resolution/members.dart b/pkg/compiler/lib/src/resolution/members.dart
index 837fb401e856eac7faa3df939601f43bd8be2c8a..4fae13c1eb30e384b5db923b9dbd89d73a4dd3e6 100644
--- a/pkg/compiler/lib/src/resolution/members.dart
+++ b/pkg/compiler/lib/src/resolution/members.dart
@@ -2318,11 +2318,20 @@ class ResolverVisitor extends MappingVisitor<ResolutionResult> {
           //   is equivalent to `this.id(a1 , ...)`.
           bool inInitializer = enclosingElement.isGenerativeConstructor ||
               (enclosingElement.isInstanceMember && enclosingElement.isField);
-          MessageKind kind = inInitializer
-              ? MessageKind.CANNOT_RESOLVE_IN_INITIALIZER
-              : MessageKind.CANNOT_RESOLVE;
-          element = reportAndCreateErroneousElement(node, node.source, kind,
-              {'name': node.source}, isError: inInitializer);
+          MessageKind kind;
+          Map arguments = {'name': name};
+          if (inInitializer) {
+            kind = MessageKind.CANNOT_RESOLVE_IN_INITIALIZER;
+          } else if (name == 'await') {
+            kind = MessageKind.CANNOT_RESOLVE_AWAIT;

[Johnni Winther, 2015/04/17 18:01:31]

Due to localization (if ever needed) we try not to create message wording
dynamically (we only insert names from the codes or word from Dart language
terminology). Use a specialized message instead.

[Siggi Cherem (dart-lang), 2015/04/17 20:58:51]

Ah, I see. I went ahead and divided the message in two specialized messages for
each case, so we don't have any text included here.

+            arguments['enclosingFunctionText'] = enclosingElement.name == ''
+                ? 'the enclosing function'
+                : "'${enclosingElement.name}'";
+          } else {
+            kind = MessageKind.CANNOT_RESOLVE;
+          }
+          element = reportAndCreateErroneousElement(node, name, kind,
+              arguments, isError: inInitializer);
           registry.registerThrowNoSuchMethod();
         }
       } else if (element.isErroneous) {