Make the RenderViewHostImpl update its visibility after a swap.

content/browser/renderer_host/render_widget_host_view_gtk.cc

Index: content/browser/renderer_host/render_widget_host_view_gtk.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_gtk.cc b/content/browser/renderer_host/render_widget_host_view_gtk.cc
index 1fe5d4c3e54070707a1b091f05efc165ce15b2f1..5f11fce910bba13849a7532a1088ad1b6eeb96db 100644
--- a/content/browser/renderer_host/render_widget_host_view_gtk.cc
+++ b/content/browser/renderer_host/render_widget_host_view_gtk.cc
@@ -689,6 +689,8 @@ void RenderWidgetHostViewGtk::WasShown() {
   if (web_contents_switch_paint_time_.is_null())
     web_contents_switch_paint_time_ = base::TimeTicks::Now();
   is_hidden_ = false;
+
+  DCHECK(host_);
   host_->WasShown();
 }
 
@@ -703,6 +705,7 @@ void RenderWidgetHostViewGtk::WasHidden() {
 
   // If we have a renderer, then inform it that we are being hidden so it can
   // reduce its resource utilization.
+  DCHECK(host_);
   host_->WasHidden();
 
   web_contents_switch_paint_time_ = base::TimeTicks();
@@ -792,10 +795,12 @@ bool RenderWidgetHostViewGtk::IsSurfaceAvailableForCopy() const {
 
 void RenderWidgetHostViewGtk::Show() {
   gtk_widget_show(view_.get());
+  WasShown();
 }
 
 void RenderWidgetHostViewGtk::Hide() {
   gtk_widget_hide(view_.get());
+  WasHidden();
 }
 
 bool RenderWidgetHostViewGtk::IsShowing() {