ColorSpaces have native SkColorSpaces

Bug: 120904891
Bug: 122844033
Bug: 122514935
Test: CtsGraphicsTestCases

Create an SkColorSpace when creating an android.graphics.ColorSpace.Rgb.
This allows simplifying getNativeColorSpace, so that each time we need
it, we do not need to call back up into Java or reconstruct the
SkColorSpace.

Funnel all ColorSpace.Rgb constructors into one, so we can set a final
mNativePtr in the base constructor. Update TransferParameters to also be
final.

Use the same TransferParameters as SRGB in EXTENDED_SRGB and DISPLAY_P3.

When passing a BitmapFactory.Options to native, call getNativeInstance()
(which may throw an Exception) and pass the result to native.

Move native ColorSpace code into its own file.

Make Paint methods @CriticalNative again, now that they do not need the
JNIEnv.

Remove unused decodeBitmap.

Change-Id: I60adbb060b87ab6f92559f1217bfefc0b9ea72e1