Remove Compiler.assembledCode.

tests/compiler/dart2js/exit_code_test.dart

Index: tests/compiler/dart2js/exit_code_test.dart
diff --git a/tests/compiler/dart2js/exit_code_test.dart b/tests/compiler/dart2js/exit_code_test.dart
index 9966f59feb6ebda835dd8c0899ce6c35087daf44..9b31127e2fe649310fadbe9e32313d60838a8e23 100644
--- a/tests/compiler/dart2js/exit_code_test.dart
+++ b/tests/compiler/dart2js/exit_code_test.dart
@@ -152,14 +152,15 @@ Future testExitCode(String marker, String type, int expectedExitCode) {
     }
   }
   return new Future(() {
-    Future<String> compile(Uri script,
-                           Uri libraryRoot,
-                           Uri packageRoot,
-                           api.CompilerInputProvider inputProvider,
-                           api.DiagnosticHandler handler,
-                           [List<String> options = const [],
-                            api.CompilerOutputProvider outputProvider,
-                            Map<String, dynamic> environment = const {}]) {
+    Future<api.CompilationResult> compile(
+        Uri script,
+        Uri libraryRoot,
+        Uri packageRoot,
+        api.CompilerInputProvider inputProvider,
+        api.DiagnosticHandler handler,
+        [List<String> options = const [],
+         api.CompilerOutputProvider outputProvider,
+         Map<String, dynamic> environment = const {}]) {
       libraryRoot = Platform.script.resolve('../../../sdk/');
       outputProvider = NullSink.outputProvider;
       // Use this to silence the test when debugging:
@@ -174,19 +175,8 @@ Future testExitCode(String marker, String type, int expectedExitCode) {
                                            marker,
                                            type,
                                            onTest);
-      return compiler.run(script).then((_) {
-        String code = compiler.assembledCode;
-        if (code != null && outputProvider != null) {
-          String outputType = 'js';
-          if (options.contains('--output-type=dart')) {
-            outputType = 'dart';
-          }
-          outputProvider('', outputType)
-              ..add(code)
-              ..close();
-          code = ''; // Non-null signals success.
-        }
-        return code;
+      return compiler.run(script).then((bool success) {
+        return new api.CompilationResult(compiler, isSuccess: success);
       });
     }
 
@@ -214,7 +204,9 @@ Future testExitCode(String marker, String type, int expectedExitCode) {
 
     Future result = entry.internalMain(
         ["tests/compiler/dart2js/exit_code_helper.dart"]);
-    return result.whenComplete(checkResult);
+    return result.catchError((e, s) {
+      // Capture crashes.
+    }).whenComplete(checkResult);
   });
 }