Add Quota.TimeSinceOriginEvicted UMA histogram.

storage/browser/quota/quota_manager.h

Index: storage/browser/quota/quota_manager.h
diff --git a/storage/browser/quota/quota_manager.h b/storage/browser/quota/quota_manager.h
index 3e053887b1ff41fb41810af6b5bfa9f134f6aa3d..5ea598c42b01b9886ab453e1721729b3c49870b6 100644
--- a/storage/browser/quota/quota_manager.h
+++ b/storage/browser/quota/quota_manager.h
@@ -204,6 +204,7 @@ class STORAGE_EXPORT QuotaManager
   virtual void DeleteOriginData(const GURL& origin,
                                 StorageType type,
                                 int quota_client_mask,
+                                bool is_eviction,
                                 const StatusCallback& callback);
   void DeleteHostData(const std::string& host,
                       StorageType type,
@@ -266,6 +267,8 @@ class STORAGE_EXPORT QuotaManager
 
   static const int kEvictionIntervalInMilliSeconds;
 
+  static const char kTimeSinceOriginEvictedHistogram[];
+
   // These are kept non-const so that test code can change the value.
   // TODO(kinuko): Make this a real const value and add a proper way to set
   // the quota for syncable storage. (http://crbug.com/155488)
@@ -363,7 +366,9 @@ class STORAGE_EXPORT QuotaManager
 
   // Methods for eviction logic.
   void StartEviction();
-  void DeleteOriginFromDatabase(const GURL& origin, StorageType type);
+  void DeleteOriginFromDatabase(const GURL& origin,
+                                StorageType type,
+                                bool is_eviction);
 
   void DidOriginDataEvicted(QuotaStatusCode status);