Speed up SimpleCache eviction set computation

net/disk_cache/simple/simple_index.h

Index: net/disk_cache/simple/simple_index.h
diff --git a/net/disk_cache/simple/simple_index.h b/net/disk_cache/simple/simple_index.h
index 7758d91362ab14882989e9ee19e05628fe108d53..b4926e51825ccc91e120485a3e5f219c4083896a 100644
--- a/net/disk_cache/simple/simple_index.h
+++ b/net/disk_cache/simple/simple_index.h
@@ -51,6 +51,10 @@ class NET_EXPORT_PRIVATE EntryMetadata {
   base::Time GetLastUsedTime() const;
   void SetLastUsedTime(const base::Time& last_used_time);
 
+  uint32_t RawTimeForSorting() const {
+    return last_used_time_seconds_since_epoch_;
+  }
+
   uint32_t GetEntrySize() const;
   void SetEntrySize(base::StrictNumeric<uint32_t> entry_size);
 
@@ -135,6 +139,10 @@ class NET_EXPORT_PRIVATE SimpleIndex
                                const EntryMetadata& entry_metadata,
                                EntrySet* entry_set);
 
+  // For use in tests only.
+  void InsertEntryForTesting(uint64_t entry_hash,
+                             const EntryMetadata& entry_metadata);
+
   // Executes the |callback| when the index is ready. Allows multiple callbacks.
   int ExecuteWhenReady(const net::CompletionCallback& callback);