Revert "Initial checkin of SkSL lexical analyzer generator (not actually in use yet)."

This reverts commit 3de0e496b5215bcf4b26db2d69dc84376dfd68d2.

Reason for revert: Google3 roll failure

Original change's description:
> Initial checkin of SkSL lexical analyzer generator (not actually in use yet).
> 
> Bug: skia:
> Change-Id: I283feb9ac1cef134588204107ea019ce657e37b3
> Reviewed-on: https://skia-review.googlesource.com/42084
> Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com,ethannicholas@google.com

Change-Id: Ifa9a054aba9baa1e0d17309a2e1838b5d3b0bfec
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/43340
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
14 files changed