Add null checks for GrSkSLtoGLSL to GrGLProgramBuilder

Bug: chromium:845351
Change-Id: I06c4114f9b2cd0609fcf7b7ce6d4a80a00ca85c3
Reviewed-on: https://skia-review.googlesource.com/131525
Auto-Submit: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
1 file changed