Fix input when hardware renderer drawing is disabled.

When drawing is disabled the window's layer won't have a valid buffer. This
causes surfaceflinger to set the window's touchableRegion to zero.
This commit sets a window crop when drawing is disabled, so surfaceflinger
set touchableregion from crop instead of buffer.
And it modifies LetterboxUiController to not reset the crop.

Test: cts and perf tests as documented in go/android-slimulator-dev-env
Bug: 229870984
Change-Id: I4d6ca513c3daf5818ded03eae00e551fc319ad69