.. from a StackTraceFrameIterator (STFI). This replaces the (incorrect)
pattern

 StackTraceFrameIterator it(isolate);
 FrameSummary fs = FrameSummary::GetTop(it.javascript_frame());

The STFI has filtering semantics that only iterate over certain JS and
Wasm frames. These semantics (e.g. skipping over frames that are not
subject to debugging) must be preserved when looking into inlined
optimized frames.

The new convenience function GetTopValidFrame encapsulates this logic.

Bug: chromium:1237730
Change-Id: I060b36b5ac6a5decef90da4de45e679516ff93fd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3110611Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76445}