Support tracking focused element for OOPIFs.

content/browser/frame_host/render_frame_host_delegate.h

Index: content/browser/frame_host/render_frame_host_delegate.h
diff --git a/content/browser/frame_host/render_frame_host_delegate.h b/content/browser/frame_host/render_frame_host_delegate.h
index 998a687d8b08250b483c20bd94b5df641f1316d8..55b0de71e3955cbbd5cea85509c3429c91213bbb 100644
--- a/content/browser/frame_host/render_frame_host_delegate.h
+++ b/content/browser/frame_host/render_frame_host_delegate.h
@@ -36,6 +36,10 @@ class GeolocationServiceContext;
 class WakeLockServiceContext;
 }
 
+namespace gfx {
+class Rect;
+}
+
 namespace content {
 class FrameTreeNode;
 class InterstitialPage;
@@ -213,6 +217,14 @@ class CONTENT_EXPORT RenderFrameHostDelegate {
   virtual std::unique_ptr<WebUIImpl> CreateWebUIForRenderFrameHost(
       const GURL& url);
 
+  // Called by |frame| to notify that it has received an update on focused
+  // element. |bounds_in_root_view| is the rectangle containing the element that
+  // is focused and is with respect to root frame's RenderWidgetHost's
+  // coordinate space.
+  virtual void OnFocusedElementChangedInFrame(
+      RenderFrameHostImpl* frame,
+      const gfx::Rect& bounds_in_root_view) {}
+
  protected:
   virtual ~RenderFrameHostDelegate() {}
 };