Add jophba@ as cast owner

This patch adds jophba@chromium.org as an owner to several cast
directories, especially mirroring and remoting related code.

Change-Id: I29a35b5ba7f957faf04bb6b5e6acc44ccfc95396
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2605389Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Yuri Wiitala <miu@chromium.org>
Commit-Queue: Jordan Bayles <jophba@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840236}

chrome/browser/extensions/api/tab_capture/OWNERS

+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

components/mirroring/OWNERS

+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

components/viz/service/frame_sinks/video_capture/OWNERS

+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

media/audio/OWNERS

@@ -5,5 +5,6 @@ olka@chromium.org
 henrika@chromium.org
 
 # Mirroring (and related glue) OWNERS.
+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

media/capture/content/OWNERS

+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

media/cast/OWNERS

+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org

media/remoting/OWNERS

 erickung@chromium.org
+jophba@chromium.org
 miu@chromium.org
 mfoltz@chromium.org