[blink/bindings] Don't try to create current directory.

`scripts/utilities.py`'s `write_file()` did not handle the case where
the file being written is in the current directory.

Bug: None
Change-Id: I3bb294aa1c45ed3caed9153e2cbb6e73d151391c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2055424
Auto-Submit: Asanka Herath <asanka@chromium.org>
Commit-Queue: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#741298}

third_party/blink/renderer/bindings/scripts/utilities.py

@@ -311,7 +311,7 @@ def write_file(new_text, destination_filename):
                 return
 
     destination_dirname = os.path.dirname(destination_filename)
-    if not os.path.exists(destination_dirname):
+    if destination_dirname and not os.path.exists(destination_dirname):
         os.makedirs(destination_dirname)
     # Write file in binary so that when run on Windows, line endings are not
     # converted