Move history API out of experimental. Allow extensions to override history page.

chrome/browser/extensions/extension_history_api.cc

Index: chrome/browser/extensions/extension_history_api.cc
diff --git a/chrome/browser/extensions/extension_history_api.cc b/chrome/browser/extensions/extension_history_api.cc
index 7edbf14d25142c3e85ca665b169444a9ee19046b..1614a801d00b5e4902326329e88fd0691fcbdaef 100644
--- a/chrome/browser/extensions/extension_history_api.cc
+++ b/chrome/browser/extensions/extension_history_api.cc
@@ -49,8 +49,10 @@ void GetVisitInfoDictionary(const history::VisitRow& row,
   value->SetReal(keys::kVisitTime, MilliSecondsFromTime(row.visit_time));
   value->SetString(keys::kReferringVisitId,
                    Int64ToString(row.referring_visit));
-  value->SetInteger(keys::kTransition,
-                    row.transition && PageTransition::CORE_MASK);
+
+  const char* trans = PageTransition::CoreTransitionString(row.transition);
+  DCHECK(trans) << "Invalid transition.";
+  value->SetString(keys::kTransition, trans);
 }
 
 void AddVisitNode(const history::VisitRow& row, ListValue* list) {