Electron Releases

Fixes #53789.

#52964 gave each nodeIntegrationInSubFrames frame its own NodeBindings, whose dummy_uv_handle_ is only initialized by the task that first runs the frame's loop. A frame removed before that task runs (Meta Pixel's hidden form POST iframes hit this) destroyed a uv_async_t that never went through uv_async_init(), so uv_close() ran on uninitialized memory: a DCHECK in testing builds, heap corruption and an eventual renderer crash in release.

• UvHandle value-initializes its handle, and reset() frees one that was never initialized (still UV_UNKNOWN_HANDLE) instead of closing it.
• New spec: the preload removes its own frame from a task queued while the frame's environment is created, which always lands before the loop's first run. It failed 21/21 without the fix (on an older nightly and on current main) and passes 10/10 with it.

Notes: Fixed a renderer crash when an iframe was removed right after loading with nodeIntegrationInSubFrames enabled and sandbox disabled, e.g. on pages that embed Meta Pixel.