Implementation of beginning of Declarative Web Request API backend

chrome/browser/extensions/api/declarative/url_matcher.h

Index: chrome/browser/extensions/api/declarative/url_matcher.h
diff --git a/chrome/browser/extensions/api/declarative/url_matcher.h b/chrome/browser/extensions/api/declarative/url_matcher.h
index ee145a974e9a6c565720f78f708557609774fc4f..4ea7f66740757b3c0fd4228f3fc95e31ae954a74 100644
--- a/chrome/browser/extensions/api/declarative/url_matcher.h
+++ b/chrome/browser/extensions/api/declarative/url_matcher.h
@@ -221,6 +221,9 @@ class URLMatcher {
   void RemoveConditionSets(
       const std::vector<URLMatcherConditionSet::ID>& condition_set_ids);
 
+  // Removes all unused condition sets from the ConditionFactory.
+  void ClearUnusedConditionSets();
+
   // Returns the IDs of all URLMatcherConditionSet that match to this |url|.
   std::set<URLMatcherConditionSet::ID> MatchURL(const GURL& url);