Determine the dataspace of the screenshot buffer based on display color mode.

Previously when we capture layers into graphic buffer we always assume SRGB
dataspace, however, if we have an app that is in wide color gamut mode, we want
to show the difference. This patch adds the ability to determine the dataspace
screenshot graphic buffer based on the color mode of the display.

BUG: 116112787
Test: Build, flash and boot. Verify with WCG Photos.
Change-Id: Ie2df32cad056576c256b9299a67855ed73714f50