ANGLE's mid-execution capture was failing after changes to
defer clears. There were still textures with pending updates
and dirty bits after SwapBuffers. This caused our calls to
Texture::getTexImage to assert.
This was due to a bug where getTexImage was not syncing state.
This change makes the function non-const so that it can update
state directly.
TBR=cnorthrop@google.com,courtneygo@google.com,jmadill@chromium.org
Test: Manhattan MEC
Bug: angleproject:4517
Change-Id: I717ad44cfc60ae0d4483721f1c91e47c5dda3939
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2186170Reviewed-by: Cody Northrop <cnorthrop@google.com>
Commit-Queue: Cody Northrop <cnorthrop@google.com>
