Fix build issues preventing Dawn DEPS from rolling

Refactoring calls to explicitly build layout group entries, so that
changes to the struct do no break the build.

An example of the types of failures being seen,
https://skia-review.googlesource.com/c/skia/+/344795

Change-Id: Iadd091e399580a743bb9cd5ab65fada84eadaf9d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/344959
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: Stephen White <senorblanco@google.com>
Auto-Submit: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@google.com>
1 file changed