Make implicit things explicit when loading scripts.

runtime/bin/dartutils.h

Index: runtime/bin/dartutils.h
diff --git a/runtime/bin/dartutils.h b/runtime/bin/dartutils.h
index 026b83a422f69622ac7f997fd289120a107b1cb2..4dc44e006d38a9ea0ca1050ff6c9547d8691a29d 100644
--- a/runtime/bin/dartutils.h
+++ b/runtime/bin/dartutils.h
@@ -122,7 +122,7 @@ class DartUtils {
                                        Dart_Handle url);
   static Dart_Handle LoadScript(const char* script_uri,
                                 Dart_Handle builtin_lib);
-  static Dart_Handle LoadScriptHttp(Dart_Handle script_uri,
+  static Dart_Handle LoadScriptHttp(Dart_Handle uri,
                                     Dart_Handle builtin_lib);
   static Dart_Handle LoadSource(CommandLineOptions* url_mapping,
                                 Dart_Handle library,
@@ -163,12 +163,23 @@ class DartUtils {
   static const char* MapLibraryUrl(CommandLineOptions* url_mapping,
                                    const char* url_string);
 
+  static Dart_Handle SetWorkingDirectory(Dart_Handle builtin_lib);
+
   static Dart_Handle ResolveScriptUri(Dart_Handle script_uri,
                                       Dart_Handle builtin_lib);
 
   static Dart_Handle FilePathFromUri(Dart_Handle script_uri,
                                      Dart_Handle builtin_lib);
 
+  static Dart_Handle PathFromUri(Dart_Handle script_uri,
+                                 Dart_Handle builtin_lib);
+
+  static Dart_Handle HostFromUri(Dart_Handle script_uri,
+                                 Dart_Handle builtin_lib);
+
+  static Dart_Handle PortFromUri(Dart_Handle script_uri,
+                                 Dart_Handle builtin_lib);
+
   static Dart_Handle ResolveUri(Dart_Handle library_url,
                                 Dart_Handle url,
                                 Dart_Handle builtin_lib);