textureSize requires the view to reflect actual mip levels, so
we can't artificially limit the view based on filtering mode.
This CL removes those views.

That unearthed a problem where the VK backend wasn't properly
implementing non-mipmapped filter modes. There is a blurb in
the Vulkan spec about this:

  There are no Vulkan filter modes that directly correspond to OpenGL
  minification filters of GL_LINEAR or GL_NEAREST, but they can be
  emulated using VK_SAMPLER_MIPMAP_MODE_NEAREST, minLod = 0, and
  maxLod = 0.25, and using minFilter = VK_FILTER_LINEAR or
  minFilter = VK_FILTER_NEAREST, respectively.

So this CL also adds that emulation.

Bug: angleproject:3948
Test: TextureSizeTextureArrayTest.BaseLevelVariesInTextureArray
Test: dEQP-GLES3.functional.shaders.texture_functions.texturesize.*
Change-Id: I81d5c3417e7d9abd0cdd058b935963706024a28f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1835937Reviewed-by: Tim Van Patten <timvp@google.com>
Commit-Queue: Cody Northrop <cnorthrop@google.com>