[graphite] Ignore no-op nodes when lifting shader expressions
This also adds a "max varyings" field to Caps, and logic to set this new
field in each backend. Expressions will only be lifted as long as there
are available varyings to pass the expression's resolved value.
Bug: b/408241870
Change-Id: I9fc4b7048765602553e05cb731e55f4ae7b0cf72
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/977956
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: James Godfrey-Kittle <jamesgk@google.com>
11 files changed
