1766971 - Review json-streaming code that could skip adjacent entries of the same type

Status: NEW

(Core :: Gecko Profiler, task, P2)

Description

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Bug 1763176 showed a problem when two counters were adjacent, because of code like this:

while (e.Has) {
  if (e.Get().IsCounterId()) {
    e.Next();
    // ... Read counter's payload entries.
  }
  e.Next(); // <-- Unconditional! Could skip the next counter if we've just read one.
}

I'm afraid there could be other instances of this pattern, we should review the whole streaming code to catch these, if any.