Vulkan: Support binding 2D slice of a 3D texture to an image unit Support binding a 3d texture as a 2d texture by specifying that it is non-layered during glBindImageTexture and expose support for EGL_KHR_gl_texture_3D_image when VK_EXT_image_2d_view_of_3d vulkan extension is supported. Tests: ComputeShaderTest.BindImageTexture3D dEQP-GLES31.functional.image_load_store.3d.*single_layer Bug: angleproject:7320 Change-Id: Ie2f0dfcdf302a4aa58990f74329ca36e62cd3902 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3648586 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: mohan maiya <m.maiya@samsung.com> Reviewed-by: Jamie Madill <jmadill@chromium.org>