Roll Observatory packages and add a roll script

packages/analyzer/lib/source/sdk_ext.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 source.sdk_ext;
 
 import 'dart:convert';
 import 'dart:core' hide Resource;
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/java_io.dart' show JavaFile;
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart' show FileBasedSource;
 import 'package:path/path.dart' as pathos;
 
 /// Given a packageMap (see [PackageMapProvider]), check in each package's lib
 /// directory for the existence of a `_sdkext` file. This file must contain a
 /// JSON encoded map. Each key in the map is a `dart:` library name. Each value
 /// is a path (relative to the directory containing `_sdkext`) to a dart script
 /// for the given library. For example:
 /// {
 ///   "dart:sky": "../sdk_ext/dart_sky.dart"
 /// }
 ///
 /// If a key doesn't begin with `dart:` it is ignored.
 class SdkExtUriResolver extends UriResolver {
   static const String SDK_EXT_NAME = '_sdkext';
   static const String DART_COLON_PREFIX = 'dart:';
 
-  final Map<String, String> _urlMappings = <String,String>{};
+  final Map<String, String> _urlMappings = <String, String>{};
 
   /// Construct a [SdkExtUriResolver] from a package map
   /// (see [PackageMapProvider]).
   SdkExtUriResolver(Map<String, List<Folder>> packageMap) {
     if (packageMap == null) {
       return;
     }
     packageMap.forEach(_processPackage);
   }
 
   /// Number of sdk extensions.
   int get length => _urlMappings.length;
 
   /// Return the path mapping for [libName] or null if there is none.
-  String operator[](String libName) => _urlMappings[libName];
+  String operator [](String libName) => _urlMappings[libName];
 
   /// Programmatically add a new SDK extension given a JSON description
   /// ([sdkExtJSON]) and a lib directory ([libDir]).
   void addSdkExt(String sdkExtJSON, Folder libDir) {
     _processSdkExt(sdkExtJSON, libDir);
   }
 
   @override
-  Source resolveAbsolute(Uri importUri) {
+  Source resolveAbsolute(Uri importUri, [Uri actualUri]) {
     String libraryName = _libraryName(importUri);
     String partPath = _partPath(importUri);
     // Lookup library name in mappings.
     String mapping = _urlMappings[libraryName];
     if (mapping == null) {
       // Not found.
       return null;
     }
     // This mapping points to the main entry file of the sdk extension.
     Uri libraryEntry = new Uri.file(mapping);
     if (!libraryEntry.isAbsolute) {
       // We expect an absolute path.
       return null;
     }
 
     if (partPath != null) {
       return _resolvePart(libraryEntry, partPath, importUri);
     } else {
       return _resolveEntry(libraryEntry, importUri);
     }
   }
 
   @override
   Uri restoreAbsolute(Source source) {
-    String libraryName = _libraryName(source.uri);
-    if (_registeredSdkExtension(libraryName)) {
-      return source.uri;
+    String extensionName = _findExtensionNameFor(source.fullName);
+    if (extensionName != null) {
+      return Uri.parse(extensionName);
     }
+    // TODO(johnmccutchan): Handle restoring parts.
     return null;
   }
 
+  /// Return the extension name for [fullName] or `null`.
+  String _findExtensionNameFor(String fullName) {
+    var result;
+    _urlMappings.forEach((extensionName, pathMapping) {
+      if (pathMapping == fullName) {
+        result = extensionName;
+      }
+    });
+    return result;
+  }
+
   /// Return the library name of [importUri].
   String _libraryName(Uri importUri) {
     var uri = importUri.toString();
     int index = uri.indexOf('/');
     if (index >= 0) {
       return uri.substring(0, index);
     }
     return uri;
   }
 
@@ skipping 49 matching lines @@
   String _readDotSdkExt(Folder libDir) {
     var file = libDir.getChild(SDK_EXT_NAME);
     try {
       return file.readAsStringSync();
     } on FileSystemException {
       // File can't be read.
       return null;
     }
   }
 
-  /// Returns true if [libraryName] is a registered sdk extension.
-  bool _registeredSdkExtension(String libraryName) {
-    return _urlMappings[libraryName] != null;
-  }
-
   /// Resolve an import of an sdk extension.
   Source _resolveEntry(Uri libraryEntry, Uri importUri) {
     // Library entry.
     JavaFile javaFile = new JavaFile.fromUri(libraryEntry);
     return new FileBasedSource(javaFile, importUri);
   }
 
   /// Resolve a 'part' statement inside an sdk extension.
   Source _resolvePart(Uri libraryEntry, String partPath, Uri importUri) {
     // Library part.
     var directory = pathos.dirname(libraryEntry.path);
     var partUri = new Uri.file(pathos.join(directory, partPath));
     assert(partUri.isAbsolute);
     JavaFile javaFile = new JavaFile.fromUri(partUri);
     return new FileBasedSource(javaFile, importUri);
   }
 }