Support --ninja-extra-args with --ide=vs

Bug: 776727
Change-Id: I401f31efa5a25033999e1cf5275275c7955fa41c
Reviewed-on: https://chromium-review.googlesource.com/731323
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Brian Osman <brianosman@google.com>
Cr-Original-Commit-Position: refs/heads/master@{#512592}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 0738f52d11987091a239d61ab965e58f492516d7