[iOS][MF] Tweaks to the Manual Fallback popover

Sets the background color to white.
Changes the preffered height to 360.

Bug: 878388, 845472
Change-Id: If4ff0363808af7c373e4f70d9d664196867fdbb6
Reviewed-on: https://chromium-review.googlesource.com/c/1350967
Reviewed-by: Yi Su <[email protected]>
Commit-Queue: Javier Ernesto Flores Robles <[email protected]>
Cr-Commit-Position: refs/heads/master@{#611632}
2 files changed