Use IO loop for the compositor and media threads in the renderer on posix.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 99cb1a1c1a2d79079fe38ccedce61dd2064c0fed..671e14c612a762ffc3aa64f889530e1f03495064 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -669,7 +669,18 @@ void RenderThreadImpl::EnsureWebKitInitialized() {
 #endif
     if (!compositor_message_loop_proxy_.get()) {
       compositor_thread_.reset(new base::Thread("Compositor"));
+#if defined(OS_POSIX)
+      // Workaround for crbug.com/293736
+      // On Posix, MessagePumpDefault uses system time, so delayed tasks (for
+      // compositor scheduling) work incorrectly across system time changes
+      // (e.g.  tlsdate). So instead, use an IO loop, which uses libevent, that
+      // uses monotonic time (immune to these problems).
+      base::Thread::Options options;
+      options.message_loop_type = base::MessageLoop::TYPE_IO;
+      compositor_thread_->StartWithOptions(options);
+#else
       compositor_thread_->Start();
+#endif
 #if defined(OS_ANDROID)
       compositor_thread_->SetPriority(base::kThreadPriority_Display);
 #endif
@@ -1294,7 +1305,18 @@ RenderThreadImpl::GetMediaThreadMessageLoopProxy() {
   DCHECK(message_loop() == base::MessageLoop::current());
   if (!media_thread_) {
     media_thread_.reset(new base::Thread("Media"));
+#if defined(OS_POSIX)
+    // Workaround for crbug.com/293736
+    // On Posix, MessagePumpDefault uses system time, so delayed tasks (for
+    // compositor scheduling) work incorrectly across system time changes
+    // (e.g.  tlsdate). So instead, use an IO loop, which uses libevent, that
+    // uses monotonic time (immune to these problems).
+    base::Thread::Options options;
+    options.message_loop_type = base::MessageLoop::TYPE_IO;
+    media_thread_->StartWithOptions(options);
+#else
     media_thread_->Start();
+#endif
   }
   return media_thread_->message_loop_proxy();
 }