Deal with extension loading from packages.

runtime/bin/extensions.cc

Index: runtime/bin/extensions.cc
diff --git a/runtime/bin/extensions.cc b/runtime/bin/extensions.cc
index 244a63109f199d50da7e67b3795bd0dd87ca0878..76d7e8867376170e1452262f093a97806cd19b91 100644
--- a/runtime/bin/extensions.cc
+++ b/runtime/bin/extensions.cc
@@ -15,10 +15,7 @@
 Dart_Handle Extensions::LoadExtension(const char* extension_url,
                                       Dart_Handle parent_library) {
   char* library_path = strdup(extension_url);
-  if (!library_path || !File::IsAbsolutePath(library_path)) {
-    free(library_path);
-    return Dart_Error("unexpected error in library path");
-  }
+

[Bill Hesse, 2012/11/22 16:18:41]

Do we really want unchecked malloc (strdup) to go ahead to a null pointer error?
 Is that the accepted failure for out of C++ heap memory?

[Mads Ager (google), 2012/11/23 07:07:40]

It would be nicer to deal with it although in general there is little you can do
if a strdup of a short string fails. In that case the next step will probably
fail as well so crashing in a controlled way is usually they best you can do.
I'll restore the null pointer check in this particular case. 

   // Extract the path and the extension name from the url.
   char* last_path_separator = strrchr(library_path, '/');
   char* extension_name = last_path_separator + 1;