Fixes to get Dart VM compiling on Ubuntu 13.04, Debian Wheezy.

runtime/bin/dartutils.cc

Index: runtime/bin/dartutils.cc
diff --git a/runtime/bin/dartutils.cc b/runtime/bin/dartutils.cc
index a90694d8733b4dd010cba34fa359402940967b9b..a2fdf9d41eaa02300ea89395139c32191a8342dd 100644
--- a/runtime/bin/dartutils.cc
+++ b/runtime/bin/dartutils.cc
@@ -364,12 +364,12 @@ Dart_Handle DartUtils::ReadStringFromHttp(const char* script_uri) {
 static const uint8_t* ReadFileFully(const char* filename,
                                     intptr_t* file_len,
                                     const char** error_msg) {
+  *file_len = -1;
   void* stream = DartUtils::OpenFile(filename, false);
   if (stream == NULL) {
     SET_ERROR_MSG(error_msg, "Unable to open file: %s", filename);
     return NULL;
   }
-  *file_len = -1;
   const uint8_t* text_buffer = NULL;
   DartUtils::ReadFile(&text_buffer, file_len, stream);
   if (text_buffer == NULL || *file_len == -1) {