Fixes to patch files necessary to use the analyzer

sdk/lib/developer/profiler.dart

Index: sdk/lib/developer/profiler.dart
diff --git a/sdk/lib/developer/profiler.dart b/sdk/lib/developer/profiler.dart
index 566d0158318b3110393e148adea893da1785b170..127a48ef1d1c32eeb2f135ec6e9656d1e677b2b4 100644
--- a/sdk/lib/developer/profiler.dart
+++ b/sdk/lib/developer/profiler.dart
@@ -9,7 +9,7 @@ abstract class UserTag {
   /// The maximum number of UserTag instances that can be created by a program.
   static const MAX_USER_TAGS = 64;
 
-  factory UserTag(String label) => new _FakeUserTag(label);
+  external factory UserTag(String label);
 
   /// Label of [this].
   String get label;
@@ -19,50 +19,11 @@ abstract class UserTag {
   UserTag makeCurrent();
 
   /// The default [UserTag] with label 'Default'.
-  static UserTag get defaultTag => _FakeUserTag._defaultTag;
+  external static UserTag get defaultTag;
 }
 
-// This is a fake implementation of UserTag so that code can compile and run
-// in dart2js.
-class _FakeUserTag implements UserTag {
-  static Map _instances = {};
-
-  _FakeUserTag.real(this.label);
-
-  factory _FakeUserTag(String label) {
-    // Canonicalize by name.
-    var existingTag = _instances[label];
-    if (existingTag != null) {
-      return existingTag;
-    }
-    // Throw an exception if we've reached the maximum number of user tags.
-    if (_instances.length == UserTag.MAX_USER_TAGS) {
-      throw new UnsupportedError(
-          'UserTag instance limit (${UserTag.MAX_USER_TAGS}) reached.');
-    }
-    // Create a new instance and add it to the instance map.
-    var instance = new _FakeUserTag.real(label);
-    _instances[label] = instance;
-    return instance;
-  }
-
-  final String label;
-
-  UserTag makeCurrent() {
-    var old = _currentTag;
-    _currentTag = this;
-    return old;
-  }
-
-  static final UserTag _defaultTag = new _FakeUserTag('Default');
-}
-
-var _currentTag = _FakeUserTag._defaultTag;
-
 /// Returns the current [UserTag] for the isolate.
-UserTag getCurrentTag() {
-  return _currentTag;
-}
+external UserTag getCurrentTag();
 
 /// Abstract [Metric] class. Metric names must be unique, are hierarchical,
 /// and use periods as separators. For example, 'a.b.c'. Uniqueness is only