Inform disk cache of WebKit memory cache hits.

net/disk_cache/entry_impl.cc

Index: net/disk_cache/entry_impl.cc
diff --git a/net/disk_cache/entry_impl.cc b/net/disk_cache/entry_impl.cc
index 369ed0d64d722f8a70a96e8c4501b941e53bcf35..3aead0b0d0aae5a2922685f655d692af97a57a89 100644
--- a/net/disk_cache/entry_impl.cc
+++ b/net/disk_cache/entry_impl.cc
@@ -396,6 +396,10 @@ int EntryImpl::ReadyForSparseIOImpl(CompletionCallback* callback) {
   return sparse_->ReadyToUse(callback);
 }
 
+void EntryImpl::UpdateRankForExternalCacheHitImpl() {
+  UpdateRank(false);
+}
+
 uint32 EntryImpl::GetHash() {
   return entry_.Data()->hash;
 }
@@ -833,6 +837,10 @@ int EntryImpl::ReadyForSparseIO(net::CompletionCallback* callback) {
   return net::ERR_IO_PENDING;
 }
 
+void EntryImpl::UpdateRankForExternalCacheHit() {
+  backend_->background_queue()->UpdateRankForExternalCacheHit(this);
+}
+
 // When an entry is deleted from the cache, we clean up all the data associated
 // with it for two reasons: to simplify the reuse of the block (we know that any
 // unused block is filled with zeros), and to simplify the handling of write /