Simplify the builtin functions and get rid of unused code.

bin/main.cc

 // 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.
 
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 #include "include/dart_debugger_api.h"
@@ skipping 366 matching lines @@
   Dart_Isolate isolate =
       Dart_CreateIsolate(script_uri, main, snapshot_buffer, data, error);
   if (isolate == NULL) {
     return false;
   }
 
   Dart_EnterScope();
 
   if (snapshot_buffer != NULL) {
     // Setup the native resolver as the snapshot does not carry it.
-    Builtin::SetupLibrary(
-        Builtin::LoadAndCheckLibrary(Builtin::kBuiltinLibrary),
-        Builtin::kBuiltinLibrary);
-    Builtin::SetupLibrary(Builtin::LoadAndCheckLibrary(Builtin::kIOLibrary),
-                          Builtin::kIOLibrary);
+    Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
+    Builtin::SetNativeResolver(Builtin::kIOLibrary);
   }
 
   // Set up the library tag handler for this isolate.
   Dart_Handle result = Dart_SetLibraryTagHandler(DartUtils::LibraryTagHandler);
   CHECK_RESULT(result);
 
   // Load the specified application script into the newly created isolate.
   Dart_Handle library;
   if (use_script_snapshot) {
     if (snapshot_file == NULL) {
@@ skipping 261 matching lines @@
   Dart_ExitScope();
   // Dump symbol information for the profiler.
   DumpPprofSymbolInfo();
   // Shutdown the isolate.
   Dart_ShutdownIsolate();
   // Terminate process exit-code handler.
   Process::TerminateExitCodeHandler();
 
   return 0;
 }