Expose whether a frame is focused to the browser process

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index c2149ef974c0bae4980c7edcf7e0b79565852b37..8f998df3621b81101c3ded3a71b562b27e0c5927 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -1540,6 +1540,13 @@ void RenderFrameHostImpl::InvalidateMojoConnection() {
   service_registry_.reset();
 }
 
+bool RenderFrameHostImpl::IsFocused() {
+  return GetView()->HasFocus() &&
+         frame_tree_->GetFocusedFrame() &&
+         (frame_tree_->GetFocusedFrame() == frame_tree_node() ||
+          frame_tree_->GetFocusedFrame()->IsDescendantOf(frame_tree_node()));
+}
+
 void RenderFrameHostImpl::UpdateCrossProcessIframeAccessibility(
     const std::map<int32, int>& node_to_frame_routing_id_map) {
   for (const auto& iter : node_to_frame_routing_id_map) {