Add a SiteEngagementEvictionPolicy.

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 07106dfe5fb86d299a4c84473182a0490f536f31..3942da88ecc7ab0f332aee2c2309a1408c564378 100644
--- a/storage/browser/quota/quota_manager.h
+++ b/storage/browser/quota/quota_manager.h
@@ -69,10 +69,19 @@ struct STORAGE_EXPORT UsageAndQuota {
                 int64 available_disk_space);
 };
 
+class STORAGE_EXPORT TemporaryStorageEvictionPolicy {

[raymes, 2015/07/08 04:43:29]

Perhaps make a note that this isn't hooked up in the QuotaEvictionHandler yet?

I'm guessing the LRU scheme would eventually become a policy? Is that right?

[calamity, 2015/07/10 05:05:05]

Done.

+ public:
+  virtual void GetEvictionOrigin(const std::map<GURL, int64>& usage_map,

[raymes, 2015/07/08 04:43:29]

We should document this. I think it's good to note that this returns the /next/
origin that should be evicted based on the inputs (could even name it
GetNextEvictionOrigin or GetNextOriginToEvict). Also noting that the origin
could be empty of no origins can be or need to be evicted.

[calamity, 2015/07/10 05:05:05]

Done.

+                                 int64 global_quota,
+                                 const GetEvictionOriginCallback& callback) = 0;
+
+ protected:
+  ~TemporaryStorageEvictionPolicy() {}
+};
+
 // An interface called by QuotaTemporaryStorageEvictor.
 class STORAGE_EXPORT QuotaEvictionHandler {
  public:
-  typedef base::Callback<void(const GURL&)> GetLRUOriginCallback;
   typedef StatusCallback EvictOriginDataCallback;
   typedef base::Callback<void(QuotaStatusCode status,
                               const UsageAndQuota& usage_and_quota)>
@@ -80,9 +89,8 @@ class STORAGE_EXPORT QuotaEvictionHandler {
 
   // Returns the least recently used origin.  It might return empty
   // GURL when there are no evictable origins.
-  virtual void GetLRUOrigin(
-      StorageType type,
-      const GetLRUOriginCallback& callback) = 0;
+  virtual void GetEvictionOrigin(StorageType type,
+                                 const GetEvictionOriginCallback& callback) = 0;
 
   virtual void EvictOriginData(
       const GURL& origin,
@@ -362,14 +370,17 @@ class STORAGE_EXPORT QuotaManager
                                                int64 unlimited_usage);
 
   // QuotaEvictionHandler.
-  void GetLRUOrigin(StorageType type,
-                    const GetLRUOriginCallback& callback) override;
+  void GetEvictionOrigin(StorageType type,
+                         const GetEvictionOriginCallback& callback) override;
   void EvictOriginData(const GURL& origin,
                        StorageType type,
                        const EvictOriginDataCallback& callback) override;
   void GetUsageAndQuotaForEviction(
       const UsageAndQuotaCallback& callback) override;
 
+  void GetLRUOrigin(StorageType type,
+                    const GetEvictionOriginCallback& callback);
+
   void DidSetTemporaryGlobalOverrideQuota(const QuotaCallback& callback,
                                           const int64* new_quota,
                                           bool success);
@@ -408,7 +419,7 @@ class STORAGE_EXPORT QuotaManager
   scoped_refptr<base::SequencedTaskRunner> db_thread_;
   mutable scoped_ptr<QuotaDatabase> database_;
 
-  GetLRUOriginCallback lru_origin_callback_;
+  GetEvictionOriginCallback lru_origin_callback_;
   std::set<GURL> access_notified_origins_;
 
   QuotaClientList clients_;