Sync vertex attributs in VertexArrayWgpu. This change only sets vertex attributes within VertexArrayWgpu and sets them in the render pipeline description owned by the context. It does not yet set attributes in the output pipeline created in CreatePipeline, as vertex buffers are also not set yet. Bug: angleproject:359823692 Change-Id: I1c3848e15d790026d53d4ab5614b1125f773e06a Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5781788 Commit-Queue: Liza Burakova <liza@chromium.org> Reviewed-by: Matthew Denton <mpdenton@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org>