Revert "Remove Compiler.assembledCode."

tests/compiler/dart2js/memory_compiler.dart

Index: tests/compiler/dart2js/memory_compiler.dart
diff --git a/tests/compiler/dart2js/memory_compiler.dart b/tests/compiler/dart2js/memory_compiler.dart
index 017db0a1428b298106fc84b848977a2c40b87776..88bc8e217c5f6fd8b1ad541ed206829bdb2750db 100644
--- a/tests/compiler/dart2js/memory_compiler.dart
+++ b/tests/compiler/dart2js/memory_compiler.dart
@@ -20,8 +20,6 @@ import 'package:compiler/src/mirrors/analyze.dart';
 import 'package:compiler/src/library_loader.dart'
     show LoadedLibraries;
 
-export 'output_collector.dart';
-
 class DiagnosticMessage {
   final Uri uri;
   final int begin;
@@ -64,6 +62,41 @@ class DiagnosticCollector {
   }
 }
 
+class BufferedEventSink implements EventSink<String> {
+  StringBuffer sb = new StringBuffer();
+  String text;
+
+  void add(String event) {
+    sb.write(event);
+  }
+
+  void addError(errorEvent, [StackTrace stackTrace]) {
+    // Do not support this.
+  }
+
+  void close() {
+    text = sb.toString();
+    sb = null;
+  }
+}
+
+class OutputCollector {
+  Map<String, Map<String, BufferedEventSink>> outputMap = {};
+
+  EventSink<String> call(String name, String extension) {
+    Map<String, BufferedEventSink> sinkMap =
+        outputMap.putIfAbsent(extension, () => {});
+    return sinkMap.putIfAbsent(name, () => new BufferedEventSink());
+  }
+
+  String getOutput(String name, String extension) {
+    Map<String, BufferedEventSink> sinkMap = outputMap[extension];
+    if (sinkMap == null) return null;
+    BufferedEventSink sink = sinkMap[name];
+    return sink != null ? sink.text : null;
+  }
+}
+
 DiagnosticHandler createDiagnosticHandler(DiagnosticHandler diagnosticHandler,
                                           SourceFileProvider provider,
                                           bool showDiagnostics) {
@@ -208,7 +241,7 @@ class MemoryLoadedLibraries implements LoadedLibraries {
   bool containsLibrary(Uri uri) => copiedLibraries.containsKey(uri);
 
   @override
-  void forEachImportChain(f, {callback}) {}
+  void forEachImportChain(f) {}
 
   @override
   void forEachLibrary(f) {}