Fix compile_single_file with remoteexec

When using remoteexec, calling ninja directly instead of ninja_reclient
causes the build to hang. This also breaks compile_single_file since it
calls ninja directly. To fix this, switch it to call autoninja instead
which will take care of this and other details like using autosiso in
the near future.

Also, using autoninja has the side-effect of using a higher -j value
which can help when building a single file causes a lot of other files
to also be built.

Bug: 1502988
Change-Id: Ib86c5c820f7c53a8420973f1b83bf8e711a9af09
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5037618
Commit-Queue: Sunny Sachanandani <sunnyps@chromium.org>
Reviewed-by: Scott Lee <ddoman@chromium.org>
Auto-Submit: Sunny Sachanandani <sunnyps@chromium.org>

compile_single_file.py

@@ -59,7 +59,7 @@ def main():
 
     command = [
         'python3',
-        os.path.join(DEPOT_TOOLS_DIR, 'ninja.py'), '-C', abs_build_dir,
+        os.path.join(DEPOT_TOOLS_DIR, 'autoninja.py'), '-C', abs_build_dir,
         '%s%s' % (src_relpath, carets)
     ]
     # |shell| should be set to True on Windows otherwise the carets characters