SurfaceFlinger: Remove the duty of ColorLayer in computeCrop

There is no active buffer in ColorLayer. Computing its source crop is
nonsense and may cause unwanted behavior in HWC.

Bug: b/109829386
Test: ColorLayer can be displayed correctly.

Change-Id: Ia30bb13e932a55a5cfb0a38da2c459d53dff5e3b
2 files changed