Abstract over the type system.

pkg/analyzer/lib/src/task/dart.dart

Index: pkg/analyzer/lib/src/task/dart.dart
diff --git a/pkg/analyzer/lib/src/task/dart.dart b/pkg/analyzer/lib/src/task/dart.dart
index e81545c1e0cc4a8a9a12a2afc93013cdbb1497b1..09731f47681e55db6f2ee95f8924b31d117a4a96 100644
--- a/pkg/analyzer/lib/src/task/dart.dart
+++ b/pkg/analyzer/lib/src/task/dart.dart
@@ -2367,10 +2367,11 @@ class GenerateHintsTask extends SourceBasedAnalysisTask {
         getRequiredInput(USED_LOCAL_ELEMENTS_INPUT);
     CompilationUnitElement unitElement = unit.element;
     LibraryElement libraryElement = unitElement.library;
+    TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
     //
     // Generate errors.
     //
-    unit.accept(new DeadCodeVerifier(errorReporter));
+    unit.accept(new DeadCodeVerifier(errorReporter, new TypeSystemImpl(typeProvider)));
     // Verify imports.
     {
       ImportsVerifier verifier = new ImportsVerifier();
@@ -2394,8 +2395,7 @@ class GenerateHintsTask extends SourceBasedAnalysisTask {
     // Dart best practices.
     InheritanceManager inheritanceManager =
         new InheritanceManager(libraryElement);
-    TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
-    unit.accept(new BestPracticesVerifier(errorReporter, typeProvider));
+    unit.accept(new BestPracticesVerifier(errorReporter, typeProvider, new TypeSystemImpl(typeProvider)));
     unit.accept(new OverrideVerifier(errorReporter, inheritanceManager));
     // Find to-do comments.
     new ToDoFinder(errorReporter).findIn(unit);
@@ -3931,7 +3931,7 @@ class VerifyUnitTask extends SourceBasedAnalysisTask {
     // Use the ConstantVerifier to compute errors.
     //
     ConstantVerifier constantVerifier = new ConstantVerifier(
-        errorReporter, libraryElement, typeProvider, context.declaredVariables);
+        errorReporter, libraryElement, typeProvider, new TypeSystemImpl(typeProvider), context.declaredVariables);
     unit.accept(constantVerifier);
     //
     // Use the ErrorVerifier to compute errors.
@@ -3940,6 +3940,7 @@ class VerifyUnitTask extends SourceBasedAnalysisTask {
         errorReporter,
         libraryElement,
         typeProvider,
+        new TypeSystemImpl(typeProvider),
         new InheritanceManager(libraryElement),
         context.analysisOptions.enableSuperMixins);
     unit.accept(errorVerifier);