Handle html+mirrors

pkg/compiler/lib/src/js_backend/backend.dart

Index: pkg/compiler/lib/src/js_backend/backend.dart
diff --git a/pkg/compiler/lib/src/js_backend/backend.dart b/pkg/compiler/lib/src/js_backend/backend.dart
index 5b9b6bd5697bbce1168110936430ad3a48ee39a1..d88b33ae4059127f944cc2279228159d9dffa303 100644
--- a/pkg/compiler/lib/src/js_backend/backend.dart
+++ b/pkg/compiler/lib/src/js_backend/backend.dart
@@ -2344,9 +2344,15 @@ class JavaScriptBackend extends Backend {
 
   /// Called when [enqueuer] is empty, but before it is closed.
   bool onQueueEmpty(Enqueuer enqueuer, Iterable<ClassElement> recentClasses) {
-    // Add elements referenced only via custom elements.  Return early if any
-    // elements are added to avoid counting the elements as due to mirrors.
-    customElementsAnalysis.onQueueEmpty(enqueuer);
+    if (!compiler.options.resolveOnly) {
+      // TODO(johnniwinther): The custom element analysis eagerly enqueues
+      // elements on the codegen queue. Change to compute the data needed
+      // instead.
+
+      // Add elements referenced only via custom elements.  Return early if any
+      // elements are added to avoid counting the elements as due to mirrors.
+      customElementsAnalysis.onQueueEmpty(enqueuer);
+    }
     if (!enqueuer.queueIsEmpty) return false;
 
     noSuchMethodRegistry.onQueueEmpty();