The data_deps section for angle_vulkan was referencing a variable
that didn't exist (no warning for this). Fix the deps which also
then exposes the build problem with the layers with Clang in 32-bit.
Also fix not propagating the Win32 defines to the layer utils.

BUG=chromium:708835

Change-Id: I4a457bfabf1ca735d3f3f3d8b0f0823cfa834b84
Reviewed-on: https://chromium-review.googlesource.com/470087
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>