Adds LPM-based SQLite fuzzer

This adds a grammar-based SQLite fuzzer based on libprotobuf-mutator.
This includes fuzzing for general SQL statements, FTS3, SQL expressions,
and SQLite's printf and strftime functions.

R=metzman@chromium.org, pwnall@chromium.org

Bug: 909886
Change-Id: I2ccd4c868f9349f63b76666206ea6c5bdf78aef5
Reviewed-on: https://chromium-review.googlesource.com/c/1366875
Commit-Queue: Matthew Denton <mpdenton@chromium.org>
Commit-Queue: Max Moroz <mmoroz@chromium.org>
Reviewed-by: Max Moroz <mmoroz@chromium.org>
Reviewed-by: Jonathan Metzman <metzman@chromium.org>
Reviewed-by: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615339}
14 files changed