This patch removes RenderPassDescriptor from BeginRenderPassCmd so that
all the backends can get the data of render pass from the non-pointer
field of BeginRenderPassCmd instead. In this patch, RenderPassDescriptor
has been removed from all Dawn backends other than the virtual function
DeviceBase::CreateRenderPassDescriptor().
This patch is one of the preparations on completely removing
RenderPassDescriptorBuilder from Dawn.
BUG=dawn:6
Change-Id: I3a78f0b2d5318c2bf85858d6fbe939b7861a2cf8
Reviewed-on: https://dawn-review.googlesource.com/c/4800
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>