In Sampler::DoSample, we only guard SignalHandler::Installed before
and Sampler::Stop may happen at the same time, which may cause SIGPROF
signal handler was already restored before SIGPROF was emit and trigger
profiling timer expired. This CL changes Sampler::DoSample to use
SignalHandler::mutex() to guard the entire function and also change
the mutex to recursive mutex.

Bug: v8:12838
Change-Id: I5195742ecdbade342986755233840d7be5d83c62
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3616429Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: 王澳 <wangao.james@bytedance.com>
Cr-Commit-Position: refs/heads/main@{#80308}