third_party/WebKit/Source/bindings/core/v8/V8GCForContextDispose.cpp

/*
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#include "bindings/core/v8/V8GCForContextDispose.h"

#include "bindings/core/v8/V8PerIsolateData.h"
#include "public/platform/Platform.h"
#include "wtf/CurrentTime.h"
#include "wtf/StdLibExtras.h"
#include <v8.h>

namespace blink {

V8GCForContextDispose::V8GCForContextDispose()
    : m_pseudoIdleTimer(this, &V8GCForContextDispose::pseudoIdleTimerFired) {
  reset();
}

void V8GCForContextDispose::notifyContextDisposed(bool isMainFrame) {
  m_didDisposeContextForMainFrame = isMainFrame;
  m_lastContextDisposalTime = WTF::currentTime();
  V8PerIsolateData::mainThreadIsolate()->ContextDisposedNotification(
      !isMainFrame);
  if (m_pseudoIdleTimer.isActive())
    m_pseudoIdleTimer.stop();
}

void V8GCForContextDispose::notifyIdle() {
  double maxTimeSinceLastContextDisposal = .2;
  if (!m_didDisposeContextForMainFrame && !m_pseudoIdleTimer.isActive() &&
      m_lastContextDisposalTime + maxTimeSinceLastContextDisposal >=
          WTF::currentTime()) {
    m_pseudoIdleTimer.startOneShot(0, BLINK_FROM_HERE);
  }
}

V8GCForContextDispose& V8GCForContextDispose::instance() {
  DEFINE_STATIC_LOCAL(V8GCForContextDispose, staticInstance, ());
  return staticInstance;
}

void V8GCForContextDispose::pseudoIdleTimerFired(TimerBase*) {
  V8PerIsolateData::mainThreadIsolate()->IdleNotificationDeadline(
      monotonicallyIncreasingTime());
  reset();
}

void V8GCForContextDispose::reset() {
  m_didDisposeContextForMainFrame = false;
  m_lastContextDisposalTime = -1;
}

}  // namespace blink