First pass at asynchronous input loading in dart2js.

tests/compiler/dart2js/deprecated_features_test.dart

Index: tests/compiler/dart2js/deprecated_features_test.dart
diff --git a/tests/compiler/dart2js/deprecated_features_test.dart b/tests/compiler/dart2js/deprecated_features_test.dart
index 58d8f07c92f79cf7400bc37e6c1e1c7e1e3793e0..5032ff8ccc64d74402987ada5ea5d717461949fd 100644
--- a/tests/compiler/dart2js/deprecated_features_test.dart
+++ b/tests/compiler/dart2js/deprecated_features_test.dart
@@ -33,32 +33,32 @@ main() {
     return new Future<String>.value(source);
   }
 
-  String code = deprecatedFutureValue(
-      compile(new Uri(scheme: 'main'),
-              new Uri(scheme: 'lib', path: '/'),
-              new Uri(scheme: 'package', path: '/'),
-              provider, handler));
-  if (code == null) {
-    throw 'Compilation failed: ${messages}';
-  }
-  Expect.stringEquals(
-      // This string is composed of lines of the following format:
-      //
-      // offset<source>:path:kind: message
-      //
-      // "offset" is the character offset from the beginning of TEST_SOURCE.
-      // "source" is the substring of TEST_SOURCE that the compiler is
-      // indicating as erroneous.
-      // "path" is the URI path.
-      // "kind" is the result of calling toString on a [Diagnostic] object.
-      // "message" is the expected message as a [String].  This is a
-      // short-term solution and should eventually changed to include
-      // a symbolic reference to a MessageKind.
-      "15<part 'part.dart';>::${deprecatedMessage('missing part-of tag')}\n"
-      "0<>:/part.dart:info: Note: This file has no part-of tag, but it is being"
-      " used as a part.\n"
-      "53<()>::${deprecatedMessage('getter parameters')}\n",
-      messages.toString());
+  compile(new Uri(scheme: 'main'),
+          new Uri(scheme: 'lib', path: '/'),
+          new Uri(scheme: 'package', path: '/'),
+          provider, handler).then((code) {
+    if (code == null) {
+      throw 'Compilation failed: ${messages}';
+    }
+    Expect.stringEquals(
+        // This string is composed of lines of the following format:
+        //
+        // offset<source>:path:kind: message
+        //
+        // "offset" is the character offset from the beginning of TEST_SOURCE.
+        // "source" is the substring of TEST_SOURCE that the compiler is
+        // indicating as erroneous.
+        // "path" is the URI path.
+        // "kind" is the result of calling toString on a [Diagnostic] object.
+        // "message" is the expected message as a [String].  This is a
+        // short-term solution and should eventually changed to include
+        // a symbolic reference to a MessageKind.
+        "15<part 'part.dart';>::${deprecatedMessage('missing part-of tag')}\n"
+        "0<>:/part.dart:info: Note: This file has no part-of tag, but it is"
+        " being used as a part.\n"
+        "53<()>::${deprecatedMessage('getter parameters')}\n",
+        messages.toString());
+  });
 }
 
 deprecatedMessage(feature) {