When we detect a texture is immutable, create it with TexStorage
and populate with TexSubImage.

Test: Temple Run MEC capture and replay
Bug: b/152512564
Bug: angleproject:3662
Change-Id: I1948a0376d2634957329d1da35d60ded3608479a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2155488
Commit-Queue: Cody Northrop <cnorthrop@google.com>
Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>