CL/Vulkan: Make CommandsStateMap as self contained The `CommandsStateMap` object is used to capture all the state that needs post-processing after a command batch is finished. Making this as a standalone object. Bug: angleproject:446112158 Change-Id: I1f33741da15fe32aae06cba79650dc76426490d5 Signed-off-by: Gowtham Tammana <g.tammana@samsung.com> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6981090 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Austin Annestrand <a.annestrand@samsung.com> Reviewed-by: Geoff Lang <geofflang@chromium.org>