The resolution may be changed while the boot animation is playing.
mInitWidth and mInitHeight store the original resolution, and then the
animation coordinate and size are recalculated according to the ratio
(mWidth/mInitWidth and mHeight/mInitHeight).
Bug: 228605923
Test: change resolution and then reboot to check the animation
Change-Id: Id09490ecf7fc4b3e1a6baf073c134f357e9b327f
(cherry picked from commit 764ea04421)
Merged-In: Id09490ecf7fc4b3e1a6baf073c134f357e9b327f
85b339fb24