[IOS][Language] Language Settings - Adds a search bar to add language page

demo: https://drive.google.com/file/d/1aiJl7IfTeh_n2gbilchiaEIWNgDXeoCD/view?usp=sharing

Bug: 957688
Change-Id: Ib765a765a2f1e46911a0073089648610b0ca8bc9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1612132
Reviewed-by: Peter Lee <pkl@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Commit-Queue: Moe Ahmadi <mahmadi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661736}
3 files changed