Update MockSdk to be more consistent with the actual SDK, switch x_Driver tests to it.

pkg/analyzer/test/src/dart/analysis/base.dart

 // Copyright (c) 2016, 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.
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/visitor.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/source/package_map_resolver.dart';
 import 'package:analyzer/src/dart/analysis/byte_store.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
 import 'package:analyzer/src/dart/analysis/file_state.dart';
 import 'package:analyzer/src/dart/analysis/status.dart';
 import 'package:analyzer/src/generated/engine.dart' show AnalysisOptionsImpl;
+import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:test/test.dart';
 
-import 'physical_sdk.dart';
+import '../../context/mock_sdk.dart';
 
 /**
  * Finds an [Element] with the given [name].
  */
 Element findChildElement(Element root, String name, [ElementKind kind]) {
   Element result = null;
   root.accept(new _ElementVisitorFunctionWrapper((Element element) {
     if (element.name != name) {
       return;
     }
     if (kind != null && element.kind != kind) {
       return;
     }
     result = element;
   }));
   return result;
 }
 
 typedef bool Predicate<E>(E argument);
 
 /**
  * A function to be called for every [Element].
  */
 typedef void _ElementVisitorFunction(Element element);
 
 class BaseAnalysisDriverTest {
   final MemoryResourceProvider provider = new MemoryResourceProvider();
+  DartSdk sdk;
   final ByteStore byteStore = new MemoryByteStore();
   final FileContentOverlay contentOverlay = new FileContentOverlay();
 
   final StringBuffer logBuffer = new StringBuffer();
   PerformanceLog logger;
 
   AnalysisDriverScheduler scheduler;
   AnalysisDriver driver;
   final List<AnalysisStatus> allStatuses = <AnalysisStatus>[];
   final List<AnalysisResult> allResults = <AnalysisResult>[];
@@ skipping 34 matching lines @@
       if (c >= '0'.codeUnitAt(0) && c <= '9'.codeUnitAt(0)) {
         length++;
         continue;
       }
       break;
     }
     return length;
   }
 
   void setUp() {
+    sdk = new MockSdk(resourceProvider: provider);
     testProject = _p('/test/lib');
     testFile = _p('/test/lib/test.dart');
     logger = new PerformanceLog(logBuffer);
     scheduler = new AnalysisDriverScheduler(logger);
     driver = new AnalysisDriver(
         scheduler,
         logger,
         provider,
         byteStore,
         contentOverlay,
@@ skipping 20 matching lines @@
 class _ElementVisitorFunctionWrapper extends GeneralizingElementVisitor {
   final _ElementVisitorFunction function;
 
   _ElementVisitorFunctionWrapper(this.function);
 
   visitElement(Element element) {
     function(element);
     super.visitElement(element);
   }
 }