deps: cherry-pick 5ba9200 from V8 upstream

Original commit message:
  Fix crash when pausing in for-of loop header

  Given a for-of loop:

    for (const each of subject) {

  The bytecode generator emits the iterator.next call + done check +
  assigning to `each` all into the source position of `const each`.

  The pseudo-desugared code looks something like:

    var tmp;
    loop {
      var result = iterator.next();
      if (result.done) break;
      tmp = result.value;

      PushBlockContext;
      const each = tmp;

      // rest of the loop.
    }

  This is a problem, as the parser starts the block scope already on
  the `const each`. If the scope requires a context we can pause on
  bytecode that has or has not pushed the block context yet, while
  the source position looks the same.

  The recent addition of per-script unique scope IDs lets us fix
  this problem in the debugger: We can check if the scope ID of
  the runtime scope matches the parser scope. If not, the context
  was not pushed yet.

  The debugger already has a `HasContext` helper. We extend it to
  also check for matching scope IDs and then use `HasContext` where
  we would read variable values off the context. If the context was
  not pushed yet, we report them as 'unavailable'.

  [email protected]

  Fixed: 384413079,399002824
  Change-Id: Ia2d0008d574e7eaf6c06b640053df696014d37f8
  Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/6507402
  Reviewed-by: Leszek Swirski <[email protected]>
  Commit-Queue: Simon Zünd <[email protected]>
  Cr-Commit-Position: refs/heads/main@{#100029}

Refs: v8/v8@5ba9200
Fixes: #60580
PR-URL: #60620
Signed-off-by: Juan José Arboleda <[email protected]>

Author: juanarbol

common.gypi

@@ -38,7 +38,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.28',
+    'v8_embedder_string': '-node.29',
 
     ##### V8 defaults for Node.js #####
 

deps/v8/src/debug/debug-scopes.cc

@@ -431,6 +431,22 @@ bool ScopeIterator::DeclaresLocals(Mode mode) const {
 }
 
 bool ScopeIterator::HasContext() const {
+  // In rare cases we pause in a scope that doesn't have its context pushed yet.
+  // E.g. when pausing in for-of loop headers (see https://crbug.com/399002824).
+  //
+  // We can detect this by comparing the scope ID of the parsed scope and the
+  // runtime scope.
+  // We can skip this check for function scopes, those will have their context
+  // always pushed. Also, there is an oddity where parsing::ParseFunction
+  // produces function scopes with (-1, -1) as the start/end position,
+  // which messes up the unique ID.
+  if (current_scope_ && !current_scope_->is_function_scope() &&
+      NeedsContext() &&
+      current_scope_->UniqueIdInScript() !=
+          context_->scope_info()->UniqueIdInScript()) {
+    return false;
+  }
+
   return !InInnerScope() || NeedsContext();
 }
 
@@ -538,6 +554,11 @@ void ScopeIterator::Next() {
   MaybeCollectAndStoreLocalBlocklists();
   UnwrapEvaluationContext();
 
+  DCHECK_IMPLIES(current_scope_ && !current_scope_->is_function_scope() &&
+                     NeedsAndHasContext(),
+                 current_scope_->UniqueIdInScript() ==
+                     context_->scope_info()->UniqueIdInScript());
+
   if (leaving_closure) function_ = Handle<JSFunction>();
 }