Move all the builtin$ interceptors to a new interceptors library and shorten the names of them.

lib/compiler/implementation/compiler.dart

 // Copyright (c) 2012, 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.
 
 class WorkItem {
   final Element element;
   TreeElements resolutionTree;
   Function run;
   bool allowSpeculativeOptimization = true;
   List<HTypeGuard> guards = const <HTypeGuard>[];
@@ skipping 27 matching lines @@
   Types types;
 
   final Tracer tracer;
 
   CompilerTask measuredTask;
   Element _currentElement;
   LibraryElement coreLibrary;
   LibraryElement coreImplLibrary;
   LibraryElement isolateLibrary;
   LibraryElement jsHelperLibrary;
+  LibraryElement interceptorsLibrary;
   LibraryElement mainApp;
+
   ClassElement objectClass;
   ClassElement closureClass;
   ClassElement dynamicClass;
   ClassElement boolClass;
   ClassElement numClass;
   ClassElement intClass;
   ClassElement doubleClass;
   ClassElement stringClass;
   ClassElement functionClass;
   ClassElement nullClass;
@@ skipping 175 matching lines @@
     nullClass = lookupSpecialClass(const SourceString('Null'));
     types = new Types(dynamicClass);
     if (!coreLibValid) {
       cancel('core library does not contain required classes');
     }
   }
 
   void scanBuiltinLibraries() {
     coreImplLibrary = scanBuiltinLibrary('coreimpl');
     jsHelperLibrary = scanBuiltinLibrary('_js_helper');
+    interceptorsLibrary = scanBuiltinLibrary('_interceptors');
     coreLibrary = scanBuiltinLibrary('core');
 
-    // Since coreLibrary import the libraries "coreimpl", and
-    // "js_helper", coreLibrary is null when they are being built. So
-    // we add the implicit import of coreLibrary now. This can be
-    // cleaned up when we have proper support for "dart:core" and
-    // don't need to access it through the field "coreLibrary".
+    // Since coreLibrary import the libraries "coreimpl", "js_helper",
+    // and "interceptors", coreLibrary is null when they are being
+    // built. So we add the implicit import of coreLibrary now. This
+    // can be cleaned up when we have proper support for "dart:core"
+    // and don't need to access it through the field "coreLibrary".
     // TODO(ahe): Clean this up as described above.
     scanner.importLibrary(coreImplLibrary, coreLibrary, null);
     scanner.importLibrary(jsHelperLibrary, coreLibrary, null);
+    scanner.importLibrary(interceptorsLibrary, coreLibrary, null);
     addForeignFunctions(jsHelperLibrary);
+    addForeignFunctions(interceptorsLibrary);
 
     universe.libraries['dart:core'] = coreLibrary;
     universe.libraries['dart:coreimpl'] = coreImplLibrary;
 
     initializeSpecialClasses();
   }
 
   /** Define the JS helper functions in the given library. */
   void addForeignFunctions(LibraryElement library) {
     library.define(new ForeignElement(
@@ skipping 225 matching lines @@
   }
 
   Script readScript(Uri uri, [ScriptTag node]) {
     unimplemented('Compiler.readScript');
   }
 
   String get legDirectory() {
     unimplemented('Compiler.legDirectory');
   }
 
-  Element findHelper(SourceString name) => jsHelperLibrary.find(name);
+  Element findHelper(SourceString name)
+      => jsHelperLibrary.findLocal(name);
+  Element findInterceptor(SourceString name)
+      => interceptorsLibrary.findLocal(name);
 
   bool get isMockCompilation() => false;
 }
 
 class CompilerTask {
   final Compiler compiler;
   final Stopwatch watch;
 
   CompilerTask(this.compiler) : watch = new Stopwatch();
 
@@ skipping 44 matching lines @@
   }
 }
 
 class SourceSpan {
   final Uri uri;
   final int begin;
   final int end;
 
   const SourceSpan(this.uri, this.begin, this.end);
 }