Reapply "Implement new model for class members." and "Implement new model for interface members."

sdk/lib/_internal/compiler/implementation/use_unused_api.dart

Index: sdk/lib/_internal/compiler/implementation/use_unused_api.dart
diff --git a/sdk/lib/_internal/compiler/implementation/use_unused_api.dart b/sdk/lib/_internal/compiler/implementation/use_unused_api.dart
index f8a1f9e247d602e81a5a605cba2e256e7809d6b3..33897e0be78a904258604120b38022b9e65e4d35 100644
--- a/sdk/lib/_internal/compiler/implementation/use_unused_api.dart
+++ b/sdk/lib/_internal/compiler/implementation/use_unused_api.dart
@@ -16,6 +16,8 @@ import 'tree/tree.dart' as tree;
 
 import 'util/util.dart' as util;
 
+import 'elements/elements.dart' as elements;
+
 import 'elements/visitor.dart' as elements_visitor;
 
 import 'js/js.dart' as js;
@@ -55,6 +57,7 @@ void main(List<String> arguments) {
   useSsa(null);
   useCodeBuffer(null);
   usedByTests();
+  useElements(null, null);
 }
 
 void useConstant(dart2jslib.Constant constant, dart2jslib.ConstantSystem cs) {
@@ -175,6 +178,8 @@ usedByTests() {
   // most cases, such API can be moved to a test library.
   dart2jslib.World world = null;
   dart2jslib.Compiler compiler = null;
+  compiler.currentlyInUserCode();
+  compiler.inUserCode(null);
   type_graph_inferrer.TypeGraphInferrer typeGraphInferrer = null;
   source_file_provider.SourceFileProvider sourceFileProvider = null;
   world.hasAnyUserDefinedGetter(null);
@@ -186,3 +191,9 @@ usedByTests() {
   new universe.TypedSelector.exact(null, null);
   sourceFileProvider.readStringFromUri(null);
 }
+
+useElements(elements.ClassElement e, elements.Name n) {
+  e.lookupClassMember(null);
+  e.lookupInterfaceMember(null);
+  n.isAccessibleFrom(null);
+}