Make the long-deprecated detachDrawGlFunctor a no-op.

WebViewDelegate.detachDrawGlFunctor has been deprecated for a long time
and is never used by any version of WebView that can run on current
Android versions. Make it a no-op like the other deprecated draw functor
methods, to remove the dependency on the hidden ViewRootImpl class.

Bug: 310653407
Test: atest CtsWebkitTestCases
Flag: android.webkit.mainline_apis
Change-Id: I863e8f33ef2004cab4da57daddcdc49a92009991