Access BackendUsage through ClosedWorld

pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart

Index: pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart b/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
index 6674a2320c98ee02c9069b92bd4400d37079187e..1356bcc51ceb4ba418d95855d3ea588f5b1ace64 100644
--- a/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
@@ -93,8 +93,6 @@ class ModelEmitter {
 
   DiagnosticReporter get reporter => compiler.reporter;
 
-  InterceptorData get _interceptorData => _closedWorld.interceptorData;
-
   js.Expression constantListGenerator(js.Expression array) {
     // TODO(floitsch): remove hard-coded name.
     return js.js('makeConstList(#)', [array]);
@@ -165,7 +163,7 @@ class ModelEmitter {
         new List<DeferredFragment>.from(program.deferredFragments);
 
     FragmentEmitter fragmentEmitter = new FragmentEmitter(
-        compiler, namer, backend, constantEmitter, this, _interceptorData);
+        compiler, namer, backend, constantEmitter, this, _closedWorld);
 
     Map<DeferredFragment, _DeferredFragmentHash> deferredHashTokens =
         new Map<DeferredFragment, _DeferredFragmentHash>();
@@ -207,7 +205,8 @@ class ModelEmitter {
             program.hasSoftDeferredClasses ||
             compiler.options.experimentalTrackAllocations);
 
-    if (backend.backendUsage.requiresPreamble && !backend.htmlLibraryIsLoaded) {
+    if (_closedWorld.backendUsage.requiresPreamble &&
+        !backend.htmlLibraryIsLoaded) {
       reporter.reportHintMessage(NO_LOCATION_SPANNABLE, MessageKind.PREAMBLE);
     }