Remove unnecessary vertical parallax

If wallpaper zoom is less than 1, the available extra height for
additional crop height will be miscalculated to negative, in that case
it should be 0 extra height.

Flag: ACONFIG com.android.wallpaper.multi_crop_preview_ui_flag STAGING
Bug: 303317694
Test: set wallpaper with parallax and compare wallpaper with preview
Change-Id: Ic5c02548d1d3937e4828b87bacddc6b3fec6b31b
2 files changed