remove DISALLOW_COPY_AND_ASSIGN from apps/*

Bug: 1010217
Change-Id: I8b8759103f6f34e65d1f28ee6dde52d9a69c87f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2434364


Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: David Bienvenu <davidbienvenu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811081}