Move RendererPreferences to content/public/common and also put in the content namespace.

chrome/browser/tab_contents/background_contents.cc

Index: chrome/browser/tab_contents/background_contents.cc
===================================================================
--- chrome/browser/tab_contents/background_contents.cc	(revision 108004)
+++ chrome/browser/tab_contents/background_contents.cc	(working copy)
@@ -176,10 +176,10 @@
   delete this;
 }
 
-RendererPreferences BackgroundContents::GetRendererPrefs(
+content::RendererPreferences BackgroundContents::GetRendererPrefs(
     content::BrowserContext* browser_context) const {
   Profile* profile = Profile::FromBrowserContext(browser_context);
-  RendererPreferences preferences;
+  content::RendererPreferences preferences;
   renderer_preferences_util::UpdateFromSystemSettings(&preferences, profile);
   return preferences;
 }