Like shaders, sampling a null child will return the input color (in
this case, the output of the skia shader stage). This gives us a path
to removing the implicit input color passed to main, which is the real
goal. Using this to create more interesting color filters is also
possible, although we need to add the versions of sample() that take a
color to really unlock the potential.
Change-Id: I6a7506055120756497d7583f14d6f928180825fc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/308515
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
871aa74797