Cleanup ValidateES2CopyTexImageParameters; add test Compressed and depth formats are rejected earlier with ValidateCopyTexImageParametersBase. Added a new Texture2DTest.CopyAfterCompressed test to ensure that validation code for non-subImage case does not fail new assertions. Bug: angleproject:5731, chromium:1216276 Change-Id: I11d2ac3389418731b6cc6e2bd5c9655b1590b02d Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3122156 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>