cocoa: fix dropping of files and URLs

the problem here is that dropped files can also be treated as
NSURLPboardType instead of just NSFilenamesPboardType. the 'else if'
could never be reached and was dead code.

this basically reverts ed695ce which tried to fix multiple dropped
URLs, or rather files, and moves the filename check infront of the URL
check. the filename path can handle multiple dropped files, whereas the
URL path can only handle one dropped URL. this assumes that only one URL
can be dropped at a time. it also reverts a603543 because it's not
needed any more.

this also fixes a problem where dropped URLs from Chrome don't conform
to the NSURL class and the readObjectsForClasses method always returned
an empty URL.

Fixes #4036

video/out/cocoa/events_view.m

@@ -313,23 +313,14 @@
 - (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
 {
     NSPasteboard *pboard = [sender draggingPasteboard];
-    if ([[pboard types] containsObject:NSURLPboardType]) {
-        NSArray *pbitems = [pboard readObjectsForClasses:@[[NSURL class]]
-                            options:@{}];
-        NSMutableArray* ar = [[[NSMutableArray alloc] init] autorelease];
-        for (NSURL* url in pbitems) {
-            if ([url isFileURL]) {
-                [ar addObject:[url path]];
-            } else {
-                [ar addObject:[url absoluteString]];
-            }
-        }
-        [self.adapter handleFilesArray:ar];
-        return YES;
-    } else if ([[pboard types] containsObject:NSFilenamesPboardType]) {
+    if ([[pboard types] containsObject:NSFilenamesPboardType]) {
         NSArray *pbitems = [pboard propertyListForType:NSFilenamesPboardType];
         [self.adapter handleFilesArray:pbitems];
         return YES;
+    } else if ([[pboard types] containsObject:NSURLPboardType]) {
+        NSURL *url = [NSURL URLFromPasteboard:pboard];
+        [self.adapter handleFilesArray:@[[url absoluteString]]];
+        return YES;
     }
     return NO;
 }