Bug 873230 - Put duplicate xml files for preferences in xml/ and xml-v11/. r=wesj

--HG--
rename : mobile/android/base/resources/xml/preference_headers.xml => mobile/android/base/resources/xml-v11/preference_headers.xml
rename : mobile/android/base/resources/xml/preferences_main.xml => mobile/android/base/resources/xml-v11/preferences.xml
rename : mobile/android/base/resources/xml/preferences_content.xml => mobile/android/base/resources/xml-v11/preferences_content.xml
rename : mobile/android/base/resources/xml/preferences_general.xml => mobile/android/base/resources/xml-v11/preferences_general.xml
rename : mobile/android/base/resources/xml/preferences_privacy.xml => mobile/android/base/resources/xml-v11/preferences_privacy.xml
rename : mobile/android/base/resources/xml/preferences_nonfragment.xml.in => mobile/android/base/resources/xml/preferences.xml.in