Fix getUserMedia may get low FPS when the selected FPS is out of range of the camera FPS eg 31 fps is wanted, the supported range is [11,30] then the final FPS should be selected to be 30 instead of 11

Review URL: https://codereview.chromium.org/641293002

Cr-Commit-Position: refs/heads/master@{#301661}
2 files changed