[iOS][MF] Fix cell with extra constraint

Bug: 845472
Change-Id: Ibdcc5ead0e06decf0fc27914bea6801120cc77a9
Reviewed-on: https://chromium-review.googlesource.com/c/1356980
Reviewed-by: Yi Su <mrsuyi@chromium.org>
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612656}
1 file changed