Fix build. Fix tests.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, 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 "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "lib/stacktrace.h"
@@ skipping 5214 matching lines @@
                                         Dart_Handle source,
                                         intptr_t line_offset,
                                         intptr_t column_offset) {
   API_TIMELINE_DURATION;
   DARTSCOPE(Thread::Current());
   Isolate* I = T->isolate();
   const String& url_str = Api::UnwrapStringHandle(Z, url);
   if (url_str.IsNull()) {
     RETURN_TYPE_ERROR(Z, url, String);
   }
-  if (Dart_IsNull(resolved_url)) {
+  if (::Dart_IsNull(resolved_url)) {
     resolved_url = url;
   }
   const String& resolved_url_str = Api::UnwrapStringHandle(Z, resolved_url);
   if (resolved_url_str.IsNull()) {
     RETURN_TYPE_ERROR(Z, resolved_url, String);
   }
   const String& source_str = Api::UnwrapStringHandle(Z, source);
   if (source_str.IsNull()) {
     RETURN_TYPE_ERROR(Z, source, String);
   }
@@ skipping 1308 matching lines @@
 
 DART_EXPORT bool Dart_IsPrecompiledRuntime() {
 #if defined(DART_PRECOMPILED_RUNTIME)
   return true;
 #else
   return false;
 #endif
 }
 
 }  // namespace dart