Ignore most modifiers in PipelineStageCodeGenerator

We ought to reject all of these in the parser, but even if they slip
through, we don't want to be emitting them for the backend. This leaves
'const' until we decide how to resolve the difference in semantics
between SkSL and GLSL.

Bug: skia:11301, skia:10837
Change-Id: I62730f6f971be04bcc3d367ceb7f211436b197c6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/368256
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed