[Impeller] add embedder support for texture surface on GL(ES).

[jonahwilliams]

We have unit tests that use this feature that need to be migrated to impeller..

[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption, contact "@test-exemption-reviewer" in the #hackers channel in Discord (don't just cc them here, they won't see it!).

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