Convert most of extensions and some other random stuff to using the base namespace for Values.

printing/page_size_margins.cc

Index: printing/page_size_margins.cc
diff --git a/printing/page_size_margins.cc b/printing/page_size_margins.cc
index 0f4d4fe8f93cabe5634e76349dd5d5115352518e..a28c6ada3c84ba013b4a57b0402b11e68d0240e4 100644
--- a/printing/page_size_margins.cc
+++ b/printing/page_size_margins.cc
@@ -12,7 +12,7 @@ namespace printing {
 
 void GetCustomMarginsFromJobSettings(const base::DictionaryValue& settings,
                                      PageSizeMargins* page_size_margins) {
-  const DictionaryValue* custom_margins;
+  const base::DictionaryValue* custom_margins;
   if (!settings.GetDictionary(kSettingMarginsCustom, &custom_margins) ||
       !custom_margins->GetDouble(kSettingMarginTop,
                                  &page_size_margins->margin_top) ||