Add WorkerThread based methods for start/stop of worker threads.

content/child/webthread_impl.cc

Index: content/child/webthread_impl.cc
diff --git a/content/child/webthread_impl.cc b/content/child/webthread_impl.cc
index d53d06e061036ba3a2c8fb99c5bcee800471eb24..8ea673789206a61ec0070568bab6060fc3c6d405 100644
--- a/content/child/webthread_impl.cc
+++ b/content/child/webthread_impl.cc
@@ -88,6 +88,30 @@ bool WebThreadImpl::isCurrentThread() const {
   return thread_->thread_id() == base::PlatformThread::CurrentId();
 }
 
+void WebThreadImpl::setSharedTimerFiredFunction(
+    SharedTimerFunction timerFunction) {
+  shared_timer_function_ = timerFunction;
+}
+
+void WebThreadImpl::setSharedTimerFireInterval(double interval_seconds) {
+  // See BlinkPlatformImpl::setSharedTimerFireInterval for explanation of
+  // why ceil is used in the interval calculation.
+  int64 interval = static_cast<int64>(
+      ceil(interval_seconds * base::Time::kMillisecondsPerSecond)
+      * base::Time::kMicrosecondsPerMillisecond);
+
+  if (interval < 0)
+    interval = 0;
+
+  shared_timer_.Stop();
+  shared_timer_.Start(FROM_HERE, base::TimeDelta::FromMicroseconds(interval),
+                      this, &WebThreadImpl::OnTimeout);
+}
+
+void WebThreadImpl::stopSharedTimer() {
+  shared_timer_.Stop();
+}
+
 WebThreadImpl::~WebThreadImpl() {
   thread_->Stop();
 }