Asynchronous initialization in Simple Index.

net/disk_cache/simple/simple_disk_format.cc

Index: net/disk_cache/simple/simple_disk_format.cc
diff --git a/net/disk_cache/simple/simple_disk_format.cc b/net/disk_cache/simple/simple_disk_format.cc
index 0a254dd30a38ce311bef5ef9d9c6dc9f4bf4b4c1..a29600423eca7ce433ce1cf279c0ca45c91aacd0 100644
--- a/net/disk_cache/simple/simple_disk_format.cc
+++ b/net/disk_cache/simple/simple_disk_format.cc
@@ -71,6 +71,15 @@ void EntryMetadata::DeSerialize(const char* in_buffer,
   memcpy(out_entry_metadata, in_buffer, kEntryMetadataSize);
 }
 
+// static
+void EntryMetadata::Merge(const EntryMetadata& from,
+                          EntryMetadata* to) {
+  if (to->last_used_time == 0)
+    to->last_used_time = from.last_used_time;
+  if (to->entry_size == 0)
+    to->entry_size = from.entry_size;
+}
+
 }  // namespace SimpleIndexFile
 
 }  // namespace disk_cache