[SurfaceFlinger] Accept data space and pixel format to take screenshot.

Previously we always take screenshot in SRGB data space. However, the current
color mode of the display can be in a different color mode, and so can HWUI
render in a different color space. Thus we want to remove the assumption that
screenshot is captured in SRGB color space, and give the ability to the upper
stack to specify the color space and pixel format it wants.

BUG: 111436479
BUG: 116112787
Test: Build, flash, boot and take screenshot, observe there's no color shift.
Test: Take screenshot, verified the color profile is correct of the png.
Change-Id: I83a0682839f39a99bff6b471a33060dd570be9b0