message: Make reallocation check in symbol-table more useful.
  Print the new node to be added.
  Issues:
diff: @@ -148,7 +148,8 @@ static ReferenceComponentNode* CheckedNewChildReferenceNode(
  if (!siblings.empty()) {
  CHECK_LT(siblings.size(), siblings.capacity())
  << "\nReallocation would invalidate pointers to reference nodes at:\n"
  - << *parent << "\nFix: pre-allocate child nodes.";
  + << *parent << "\nWhile attempting to add child:\n"
  + << component << "\nFix: pre-allocate child nodes.";
  }
  // Otherwise, this first node had no prior siblings, so no need to check.
  return parent->NewChild(component); // copy
  