evict larger entries first

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 6740c2c91e2b810caa5d2092d93baff6b616c85e..f7ec11132980de17a395eeb8dc85a9d39a1bea72 100644
--- a/net/disk_cache/simple/simple_index.h
+++ b/net/disk_cache/simple/simple_index.h
@@ -70,6 +70,7 @@ class NET_EXPORT_PRIVATE EntryMetadata {
   }
 
   static const int kOnDiskSizeBytes = 16;
+  static const int kEstimatedEntryOverhead = 512;
 
  private:
   friend class SimpleIndexFileTest;