Update Lexer#number monkey patch

This monkey patch was resulting in invalid parse trees being generated.

We knew this was a risk when we first introduced this. Fix it by
patching again for now, but we'll try to follow up with a solution that
doesn't require patching.

Change-Id: Ied78602cbfd273a36d6222f12f3968ddd0827a67
Reviewed-on: http://gerrit.causes.com/36423
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>