[dawn][native] Add DynamicArrayState default bindings

The default bindings are used instead of the dynamic array element when
!hasBinding<T>. They are inserted at the end of the dynamic binding
array, after all of the slots for the users' bindings. This CL:

 - Adds creation of all 26 default bindings for
   wgpu::DynamicBindingKind::SampledTexture. This is cached on a
   DynamicArrayDefaultBindings object.
 - Makes the DynamicArrayDefaultBindings object part of the device so it
   can be reused between bindgroups.
 - Inserts the default bindings at the end of the DynamicArrayState
   bindings.
    - This requires updating the Vulkan backend to reserve enough space
      for the additional bindings.
    - Separately keep track of the API size of the DynamicArrayState
      since mBindings now also contains default bindings.
    - Changes the logic in DynamicArrayState metadata updates to only do
      updates for the user bindings.
      - Updates the Vulkan backend to handle empty metadata updates.
 - Pass to Tint the order in which we put the default bindings at the
   end of the binding array.
 - Adds a test that default bindings contain zeroes and have size 1
   (only for a few interesting types).
    - Fix the KeepBIndingArrayAsPointer transform to list
      DuplicateBindings as a capability.

Bug: 435317394
Change-Id: I97201f193b0136d6c5b1003e9ba6ac2598295bbf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/260255
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>