macosx: fix resume playback for file urls containing whitespaces

(cherry picked from commit 4cdf312ea0ddfb5441d05f70903c520469100032)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/gui/macosx/playlist.m

@@ -1544,7 +1544,7 @@
     if (url.length < 1)
         return;
 
-    if (![[NSURL URLWithString:url] isFileURL])
+    if ([url rangeOfString:@"file://" options:NSCaseInsensitiveSearch].location != 0)
         return;
 
     NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];