Change lookup path for Dart native extensions shared libraries.

runtime/bin/file_win.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 "bin/file.h"
 
 #include <fcntl.h>
 #include <io.h>
 #include <stdio.h>
 #include <string.h>
@@ skipping 144 matching lines @@
   }
   return true;
 }
 
 
 bool File::IsAbsolutePath(const char* pathname) {
   // Should we consider network paths?
   if (pathname == NULL) return false;
   return (strlen(pathname) > 2) &&
       (pathname[1] == ':') &&
-      (pathname[2] == '\\');
+      (pathname[2] == '\\' || pathname[2] == '/');
 }
 
 
 char* File::GetCanonicalPath(const char* pathname) {
   struct stat st;
   if (stat(pathname, &st) != 0) {
     SetLastError(ERROR_FILE_NOT_FOUND);
     return NULL;
   }
   int required_size = GetFullPathName(pathname, 0, NULL, NULL);
@@ skipping 36 matching lines @@
 const char* File::StringEscapedPathSeparator() {
   return "\\\\";
 }
 
 
 File::StdioHandleType File::GetStdioHandleType(int fd) {
   // Treat all stdio handles as pipes. The Windows event handler and
   // socket code will handle the different handle types.
   return kPipe;
 }