Register type constants through ConstantUse

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

Index: pkg/compiler/lib/src/js_backend/codegen_listener.dart
diff --git a/pkg/compiler/lib/src/js_backend/codegen_listener.dart b/pkg/compiler/lib/src/js_backend/codegen_listener.dart
index 8de2576f6b08f215dff7ae197a22dbfec32b87b7..705fbfa8a8ab46e7311f28da4042eaa3b93d2080 100644
--- a/pkg/compiler/lib/src/js_backend/codegen_listener.dart
+++ b/pkg/compiler/lib/src/js_backend/codegen_listener.dart
@@ -211,6 +211,14 @@ class CodegenEnqueuerListener extends EnqueuerListener {
     } else if (constant.isType) {
       impactBuilder
           .registerTypeUse(new TypeUse.instantiation(_backendClasses.typeType));
+      // If the type is a web component, we need to ensure the constructors are
+      // available to 'upgrade' the native object.
+      TypeConstantValue type = constant;
+      if (type.representedType.isInterfaceType) {
+        ResolutionInterfaceType representedType = type.representedType;
+        _customElementsAnalysis.registerTypeConstant(representedType.element);
+        _lookupMapAnalysis.registerTypeConstant(representedType.element);
+      }
     }
     _lookupMapAnalysis.registerConstantKey(constant);
   }