[iOS] Update iOS-specific copied content strings

This CL updates the strings for the new copied content experience on
iOS. These are the strings for using copied text/images after an
omnibox longpress and on a press of the search accelerator menu.

Bug: 703076
Change-Id: I8752ef7826717f3e97dae738291b226c6c5a340d
Reviewed-on: https://chromium-review.googlesource.com/c/1470702
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Commit-Queue: Robbie Gibson <rkgibson@google.com>
Cr-Commit-Position: refs/heads/master@{#633115}
7 files changed