UClamp.min of all threads in top app is set to mid core max capacity during photo capture, which will dispatch them to big core.
Critical threads of photo capture will be interrupted due to their lower priority, while other cores idle.
To deal with this situation,
prefer_idle mask to big/mid cores can reduce the idle in mid cores.
UClamp.min on nice can set UClamp.min of photo capture critical threads to mid core max capacity, while others as zero,
this can make critical threads run on big core without frequently interrupted.
By applying this, photo capture latency can be reduced with slight change of power consumption.
Refer to ag/28118299
Bug: 345601796
Bug: 342502377
Test: Build pass, Boot to home
Flag: NONE powerhint change does not support flags
Change-Id: I86e36c64de4fe02e9c04171edbbc642cac1d0c3c
02f1389157