Move Render(View|Widget)Host and associated classes to content namespace.

content/public/browser/render_view_host_delegate.h

Index: content/public/browser/render_view_host_delegate.h
diff --git a/content/public/browser/render_view_host_delegate.h b/content/public/browser/render_view_host_delegate.h
index 3a41689330abb3ba00abbfaca0298c4b62bb440d..bb3701e54ff9e7babdf5b8b65ccae129cbbacbcf 100644
--- a/content/public/browser/render_view_host_delegate.h
+++ b/content/public/browser/render_view_host_delegate.h
@@ -23,7 +23,6 @@
 #include "webkit/glue/window_open_disposition.h"
 
 class GURL;
-class RenderViewHost;
 class SkBitmap;
 class TabContents;
 class WebKeyboardEvent;
@@ -47,6 +46,7 @@ class Size;
 namespace content {
 
 class BrowserContext;
+class RenderViewHost;
 class WebContents;
 struct ContextMenuParams;
 struct FileChooserParams;