On some recent Android devices camera switch is completed in 400 ms.
Need to adjust key frame generation threshold to ensure HW encoder
still generates a key frame after camera switch to workaround video
distortions.
BUG=b/32238476
Review-Url: https://codereview.webrtc.org/2447163003
Cr-Commit-Position: refs/heads/master@{#14791}