WebGLRenderingContextBase preventBufferClearForInspector is redundant
<rdar://problem/117684773>
Pull request: https://github.com/WebKit/WebKit/pull/19715
Committed 270046@main (27dac32ecc9c): <https://commits.webkit.org/270046@main> Reviewed commits have been landed. Closing PR #19715 and removing active labels.