Add forceDepthAttachmentInitOnClear frontend workaround AMD on D3D11 skips depth buffer updates in some cases. Bug: angleproject:7246 Bug: angleproject:7200 Change-Id: I27bbea30fbf4173470063a670b9c43a805286c39 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3608092 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Kenneth Russell <kbr@chromium.org> Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>