Refactor strong mode to use standard Analyzer errors

pkg/analyzer/lib/src/generated/error_verifier.dart

Index: pkg/analyzer/lib/src/generated/error_verifier.dart
diff --git a/pkg/analyzer/lib/src/generated/error_verifier.dart b/pkg/analyzer/lib/src/generated/error_verifier.dart
index b7bc5942c0dc7914af1b42f97ae4f05a5359d59d..eca427d5390ccb170d4b1cab66e96d115e3eae17 100644
--- a/pkg/analyzer/lib/src/generated/error_verifier.dart
+++ b/pkg/analyzer/lib/src/generated/error_verifier.dart
@@ -30,7 +30,8 @@ import 'package:analyzer/src/generated/sdk.dart' show DartSdk, SdkLibrary;
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/task/dart.dart';
-import 'package:analyzer/src/task/strong/info.dart' show StaticInfo;
+import 'package:analyzer/src/task/strong/checker.dart' as checker
+    show isKnownFunction;
 
 /**
  * A visitor used to traverse an AST structure looking for additional errors and
@@ -5743,8 +5744,7 @@ class ErrorVerifier extends RecursiveAstVisitor<Object> {
 
   bool _expressionIsAssignableAtType(Expression expression,
       DartType actualStaticType, DartType expectedStaticType) {
-    bool concrete =
-        _options.strongMode && StaticInfo.isKnownFunction(expression);
+    bool concrete = _options.strongMode && checker.isKnownFunction(expression);
     if (concrete) {
       actualStaticType =
           _typeSystem.typeToConcreteType(_typeProvider, actualStaticType);