cleans up sdk patching so we no longer have unresolved names

tool/patch_sdk.dart

 #!/usr/bin/env 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.
 
 /// Command line tool to merge the SDK libraries and our patch files.
 /// This is currently designed as an offline tool, but we could automate it.
 library ddc.tool.patch_sdk;
 
 import 'dart:io';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:path/path.dart' as path;
 
 import 'input_sdk_src/lib/_internal/libraries.dart' as sdk;
 
 void main(List<String> argv) {
   var toolDir = path.relative(path.dirname(Platform.script.path));
   var sdkIn = path.join(toolDir, 'input_sdk_src', 'lib');
   var patchIn = path.join(toolDir, 'input_sdk_patch');
-  var sdkOut = path.join(path.dirname(toolDir), 'test', 'generated_sdk', 'lib');
+  var sdkOut =
+      path.normalize(path.join(toolDir, '..', 'test', 'generated_sdk', 'lib'));
 
   if (argv.isNotEmpty) {
     print('Usage: ${path.relative(Platform.script.path)}\n');
     print('input SDK directory: $sdkIn');
     print('input patch directory: $patchIn');
     print('output SDK directory: $sdkOut');
     exit(1);
   }
 
   // Copy libraries.dart and version
   _writeSync(path.join(sdkOut, '_internal', 'libraries.dart'),
       new File(path.join(sdkIn, '_internal', 'libraries.dart'))
           .readAsStringSync());
   _writeSync(path.join(sdkOut, '..', 'version'),
       new File(path.join(sdkIn, '..', 'version')).readAsStringSync());
 
   // Enumerate core libraries and apply patches
   for (var library in sdk.LIBRARIES.values) {
+    if (library.platforms & sdk.DART2JS_PLATFORM == 0) continue;
+
     var libraryPath = path.join(sdkIn, library.path);
+
     var libraryFile = new File(libraryPath);
     if (libraryFile.existsSync()) {
       var contents = <String>[];
       var paths = <String>[];
       var libraryContents = libraryFile.readAsStringSync();
       paths.add(libraryPath);
       contents.add(libraryContents);
       for (var part in parseDirectives(libraryContents).directives) {
         if (part is PartDirective) {
           paths.add(path.join(path.dirname(libraryPath), part.uri.stringValue));
           contents.add(new File(paths.last).readAsStringSync());
         }
       }
 
-      var patchPath = path.join(patchIn, library.dart2jsPatchPath.replaceAll(
-          '_internal/compiler/js_lib/', ''));
-      var patchContents = new File(patchPath).readAsStringSync();
+      if (library.dart2jsPatchPath != null) {
+        var patchPath = path.join(patchIn, library.dart2jsPatchPath.replaceAll(
+            '_internal/compiler/js_lib/', ''));
+        var patchContents = new File(patchPath).readAsStringSync();
 
-      contents = _patchLibrary(contents, patchContents);
+        contents = _patchLibrary(contents, patchContents);
+      }
       for (var i = 0; i < paths.length; i++) {
         var outPath = path.join(sdkOut, path.relative(paths[i], from: sdkIn));
         _writeSync(outPath, contents[i]);
       }
     }
   }
 }
 
 /// Writes a file, creating the directory if needed.
 void _writeSync(String filePath, String contents) {
@@ skipping 56 matching lines @@
     if (_isLibrary) _mergeUnpatched(node);
   }
 
   /// Merges directives and declarations that are not `@patch` into the library.
   void _mergeUnpatched(CompilationUnit unit) {
     // Merge directives from the patch
     // TODO(jmesserly): remove duplicate imports
     var directivePos = unit.directives.last.end;
     for (var directive in patch.unit.directives) {
       var uri = directive.uri.stringValue;
-      // TODO(jmesserly): figure out what to do about these
-      if (uri.startsWith('dart:_') && uri != 'dart:_internal') continue;
       var code = patch.contents.substring(directive.offset, directive.end);
       edits.insert(directivePos, '\n' + code);
     }
 
     // Merge declarations from the patch
     var declarationPos = edits.original.length;
     for (var declaration in patch.mergeDeclarations) {
       var code = patch.contents.substring(declaration.offset, declaration.end);
       edits.insert(declarationPos, '\n' + code);
     }
@@ skipping 194 matching lines @@
   int get length => end - begin;
 
   String toString() => '(Edit @ $begin,$end: "$replace")';
 
   int compareTo(_StringEdit other) {
     int diff = begin - other.begin;
     if (diff != 0) return diff;
     return end - other.end;
   }
 }