Refactor handling of unqualified static updates.

pkg/compiler/lib/src/resolution/registry.dart

Index: pkg/compiler/lib/src/resolution/registry.dart
diff --git a/pkg/compiler/lib/src/resolution/registry.dart b/pkg/compiler/lib/src/resolution/registry.dart
index 28a7ed3be224c0542cd2bac58f347aad672e25fb..552914c572a93df97820ff63795ee7ed86f8e5a9 100644
--- a/pkg/compiler/lib/src/resolution/registry.dart
+++ b/pkg/compiler/lib/src/resolution/registry.dart
@@ -569,6 +569,8 @@ class ResolutionRegistry implements Registry {
   Setlet<Element> get otherDependencies => mapping.otherDependencies;
 
   void registerStaticInvocation(Element element) {
+    // TODO(johnniwinther): Increase precision of [registerStaticUse] and
+    // [registerDependency].
     if (element == null) return;
     registerStaticUse(element);
     registerDependency(element);