Remove incorrect cast of loop condition in GLSL parsing Loop condition node may be a declaration node when coming from the parser, so it shouldn't be casted to TIntermTyped*. BUG=chromium:738281 TEST=angle_unittests under CFI Change-Id: Ie98befc4b02b1261949049ddff49404d73db8478 Reviewed-on: https://chromium-review.googlesource.com/558083 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>