Add setVisibilityState API to WebFrameWidget

Source/web/WebFrameWidgetImpl.cpp

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 996 matching lines @@
             m_layerTreeView->registerViewportLayers(nullptr, pageScaleLayer, rootScrollLayer->platformLayer(), nullptr);
         } else {
             m_layerTreeView->clearRootLayer();
             m_layerTreeView->clearViewportLayers();
         }
     }
 
     suppressInvalidations(false);
 }
 
+void WebFrameWidgetImpl::setVisibilityState(WebPageVisibilityState visibilityState, bool isInitialState)
+{
+    if (!m_page)
+        return;
+
+    ASSERT(visibilityState == WebPageVisibilityStateVisible || visibilityState == WebPageVisibilityStateHidden || visibilityState == WebPageVisibilityStatePrerender);

[Nate Chapin, 2015/02/26 21:16:34]

I agree this is wonky, but if there's precedent, I'll get over it.

[kenrb, 2015/02/26 22:29:56]

Or, I could just remove it. There is nothing I can find to suggest a really good
reason.

+    m_page->setVisibilityState(static_cast<PageVisibilityState>(visibilityState), isInitialState);

[Nate Chapin, 2015/02/26 21:16:34]

Just to make sure I understand correctly, setVisibilityState() is only called on
one WebFrameWidget per page?

[kenrb, 2015/02/26 22:29:56]

Aha, no. :(

This is what I was talking about before with confusion of page and frame level
visibility state. This has the potential to cause some visual issues when you
have multiple OOPIFs in the same process -- the Page will temporarily think it
is invisible while one OOPIF is being loaded, even though another OOPIF might be
available and rendering.

Are you okay with this if I file a bug against myself to sort this out later?

+
+    if (m_layerTreeView) {
+        bool visible = visibilityState == WebPageVisibilityStateVisible;
+        m_layerTreeView->setVisible(visible);
+    }
+}
+
 } // namespace blink