In this scenario, we allow the texStorage call to fully populate the
image, then let dirty bits change the vkImage to reflect the base level.

Bug: angleproject:3948
Bug: angleproject:3949
Test: dEQP-GLES3.functional.shaders.texture_functions.texturesize.*
Change-Id: I1f453653a23b9d1802a374def40c9372ada8822a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1841275
Commit-Queue: Cody Northrop <cnorthrop@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>