CL: Update event creation routines Move backend construction after frontend construction completes. This avoids potential undefined behavior if backend construction tries to access members of half-constructed frontend object. Add virtual onEventCreate routine for any actions that need to be performed after cmd event has been created. Additionally, this also fixes incorrect timestamp values when queue profiling is enabled for the VK backend. This was due to a missed event association to the cmd queue. Bug: angleproject:377942756 Change-Id: I0a2f0390cc04f94143d1801ad71e06f63785f3ce Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6149055 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Austin Annestrand <a.annestrand@samsung.com> Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Gowtham Tammana <g.tammana@samsung.com>