Backport SQLite memcmp patch.

http://www.sqlite.org/src/info/d73435587b

Verified that the amalgamation came out with all the right patches by
comparing the amalgamation diff to the appropriately-ordered diffs of
the original files.

BUG=178677

Review URL: https://chromiumcodereview.appspot.com/15070002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@199345 0039d316-1c4b-4281-b951-d872f2087c98
8 files changed