Add GLSL type aliases for SkRuntimeEffect SkSL

Adds vec[N], mat[N], and mat[NxM] aliases when building runtime effect
code. Also moves the "shader" alias for fragmentProcessor so it's only
usable in that context.

Bug: skia:10679
Change-Id: Ia337bb680c50da32639bb1d4ffc3bc01df306b0f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/325620
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
2 files changed