Move RemoteImageBuffer methods from RemoteRenderingBackend to RemoteImageBuffer It is customary that the methods are implemented in the class that intends to respond to the methods.
<rdar://problem/114933263>
Pull request: https://github.com/WebKit/WebKit/pull/17408
Committed 267620@main (5b609e6db647): <https://commits.webkit.org/267620@main> Reviewed commits have been landed. Closing PR #17408 and removing active labels.