Bug 164472 – REGRESSION (r192721): GC timers stop to work when Heap claims it grew

• Status: NEW
• Component: JavaScriptCore

[VaL]

Due to https://bugs.webkit.org/show_bug.cgi?id=151521
when deathRate() now returns 0 (when heap reported that e.g. m_sizeAfterLastEdenCollect > m_sizeBeforeLastEdenCollect or m_sizeAfterLastFullCollect > m_sizeBeforeLastFullCollect after garbage collecting)

GCActivityCallback::didAllocate uses 
    double bytesExpectedToReclaim = static_cast<double>(bytes) * deathRate();
    double newDelay = lastGCLength() / gcTimeSlice(bytesExpectedToReclaim);
    scheduleTimer(newDelay);
which causes newDelay to be positive inf.

GCActivityCallback::scheduleTimer configures the timer to std::chrono::microseconds::max();
and the timer never invoked.