Resume a backgrounded renderer that was purged and suspended

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 923db0079a6c2e61226eb05a69196a221674e412..21955188506da0bffd84e85715b497d11de3fb1a 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -1766,7 +1766,7 @@ void RenderThreadImpl::OnProcessBackgrounded(bool backgrounded) {
 
 void RenderThreadImpl::OnProcessPurgeAndSuspend() {
   ChildThreadImpl::OnProcessPurgeAndSuspend();
-  if (is_renderer_suspended_)
+  if (is_renderer_suspended_ || !RendererIsHidden())
     return;
   // TODO(hajimehoshi): Implement purging e.g. cache (crbug/607077)
   is_renderer_suspended_ = true;
@@ -1877,6 +1877,15 @@ void RenderThreadImpl::RecordPurgeAndSuspendMetrics() const {
                               1024 / 1024);
 }
 
+void RenderThreadImpl::OnProcessResume() {
+  ChildThreadImpl::OnProcessResume();
+  if (!is_renderer_suspended_)
+    return;
+
+  is_renderer_suspended_ = false;
+  renderer_scheduler_->ResumeRenderer();
+}
+
 scoped_refptr<gpu::GpuChannelHost> RenderThreadImpl::EstablishGpuChannelSync() {
   TRACE_EVENT0("gpu", "RenderThreadImpl::EstablishGpuChannelSync");