[iOS] Move BrowserCoordinator to the correct folder

This CL moves the BrowserCoordinator to the browser_view folder such as
it is in the same folder as BVC.

Bug: 944008
Change-Id: I6c24dd12a852547d496fc2cbb85968c8b63eeb30
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1581966
Reviewed-by: Mark Cogan <marq@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653959}
7 files changed