Normalize paths in PhysicalResourceProvider.getFile()/getFolder().

pkg/analyzer/lib/file_system/physical_file_system.dart

 // Copyright (c) 2014, 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 analyzer.file_system.physical_file_system;
 
 import 'dart:async';
 import 'dart:core' hide Resource;
 import 'dart:io' as io;
 
@@ skipping 54 matching lines @@
   PhysicalResourceProvider(String fileReadMode(String s)) {
     if (fileReadMode != null) {
       FileBasedSource.fileReadMode = fileReadMode;
     }
   }
 
   @override
   Context get pathContext => io.Platform.isWindows ? windows : posix;
 
   @override
-  File getFile(String path) => new _PhysicalFile(new io.File(path));
+  File getFile(String path) {
+    path = normalize(path);

[Brian Wilkerson, 2016/08/12 17:43:33]

Should this be "pathContext.normalize()"?

[scheglov, 2016/08/12 18:02:50]

It could be, but it does not have to.

We has "pathContext" mostly for the clients, to implement ResourceProvider.
Internally in the physical resource provider we know that "path" methods will
work as the physical file system needs.

+    return new _PhysicalFile(new io.File(path));
+  }
 
   @override
-  Folder getFolder(String path) => new _PhysicalFolder(new io.Directory(path));
+  Folder getFolder(String path) {
+    path = normalize(path);
+    return new _PhysicalFolder(new io.Directory(path));
+  }
 
   @override
   Future<List<int>> getModificationTimes(List<Source> sources) async {
     List<String> paths = sources
         .map((source) => source is FileBasedSource ? source.fullName : null)
         .toList();
     IsolateRunner runner = await pathsToTimesIsolateProvider.get();
     return runner.run(_pathsToTimes, paths);
   }
 
@@ skipping 250 matching lines @@
           timer.cancel();
         }
       });
       return completer.future;
     }
     _isSpawning = true;
     _runner = await IsolateRunner.spawn();
     return _runner;
   }
 }