Remove unused members from GLSLCodeGenerator.

Change-Id: I49ed41170d5ac39658554435f806af0218911316
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/516158
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
2 files changed