Made IRNode smaller

This backs off a bit on the "stuff everything into IRNode" push, moving
the data of the big nodes back into them and significantly cutting the
size of IRNode. This isn't a complete revert of the changes to these
nodes - now that all of the fields have been hidden behind accessor
methods, it's merely an implementation detail where the data actually
lives, so these changes are much smaller and more targeted.

Change-Id: I84c770245f26dfe36651d0f482543505bd7f71ef
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/329629
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
13 files changed