Generating separate entries for array of array members in blocks is
needed so that block member queries work correctly.

This change will be tested more fully once support for parsing arrays
of arrays lands in the compiler.

BUG=angleproject:2125

Change-Id: I052837ddd4ee44a5c2390d3af44c0f1d21fa5fc7
Reviewed-on: https://chromium-review.googlesource.com/787975Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>