Improve strong-mode implementation and fix several failing tests

pkg/analyzer/test/src/task/strong_mode_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library test.src.task.strong_mode_test;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/src/task/strong_mode.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../reflective_tests.dart';
 import '../../utils.dart';
 import '../context/abstract_context.dart';
 
 main() {
   initializeTestEnvironment();
-  runReflectiveTests(InferrenceFinderTest);
   runReflectiveTests(InstanceMemberInferrerTest);
   runReflectiveTests(VariableGathererTest);
 }
 
 @reflectiveTest
-class InferrenceFinderTest extends AbstractContextTest {
-  void test_creation() {
-    InferrenceFinder finder = new InferrenceFinder();
-    expect(finder, isNotNull);
-    expect(finder.classes, isEmpty);
-    expect(finder.staticVariables, isEmpty);
-  }
-
-  void test_visit() {
-    Source source = addSource(
-        '/test.dart',
-        r'''
-const c = 1;
-final f = '';
-var v = const A();
-int i;
-class A {
-  static final fa = 0;
-  static int fi;
-  const A();
-}
-class B extends A {
-  static const cb = 1;
-  static vb = 0;
-  const ci = 2;
-  final fi = '';
-  var vi;
-}
-class C = Object with A;
-typedef int F(int x);
-''');
-    LibrarySpecificUnit librarySpecificUnit =
-        new LibrarySpecificUnit(source, source);
-    computeResult(librarySpecificUnit, RESOLVED_UNIT5);
-    CompilationUnit unit = outputs[RESOLVED_UNIT5];
-    InferrenceFinder finder = new InferrenceFinder();
-    unit.accept(finder);
-    expect(finder.classes, hasLength(3));
-    expect(finder.staticVariables, hasLength(6));
-  }
-}
-
-@reflectiveTest
 class InstanceMemberInferrerTest extends AbstractContextTest {
   InstanceMemberInferrer get createInferrer =>
       new InstanceMemberInferrer(context.typeProvider);
 
   /**
    * Add a source with the given [content] and return the result of resolving
    * the source.
    */
   CompilationUnitElement resolve(String content) {
     Source source = addSource('/test.dart', content);
@@ skipping 865 matching lines @@
     }
   }
 }
 ''');
     CompilationUnit unit = context.resolveCompilationUnit2(source, source);
     VariableGatherer gatherer = new VariableGatherer(filter);
     unit.accept(gatherer);
     return gatherer.results;
   }
 }