Fix IndexedDB race condition during shutdown.

chrome/browser/in_process_webkit/indexed_db_key_utility_client.h

Index: chrome/browser/in_process_webkit/indexed_db_key_utility_client.h
diff --git a/chrome/browser/in_process_webkit/indexed_db_key_utility_client.h b/chrome/browser/in_process_webkit/indexed_db_key_utility_client.h
index 3a79c282be520b8bfa973c23b68d6a2eb96b9e04..20887ead277dc12d6346ba7ef22965988a7bc037 100644
--- a/chrome/browser/in_process_webkit/indexed_db_key_utility_client.h
+++ b/chrome/browser/in_process_webkit/indexed_db_key_utility_client.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include "base/ref_counted.h"
+#include "base/synchronization/lock.h"
 #include "base/synchronization/waitable_event.h"
 #include "chrome/browser/utility_process_host.h"
 
@@ -21,17 +22,12 @@ class SerializedScriptValue;
 class IndexedDBKeyUtilityClient
     : public base::RefCountedThreadSafe<IndexedDBKeyUtilityClient> {
  public:
-  IndexedDBKeyUtilityClient();
 
-  // Starts the UtilityProcess. Must be called before any other method.
-  void StartUtilityProcess();
+  // Get a pointer to the IndexedDBKeyUtilityClient instance.
+  static IndexedDBKeyUtilityClient* Get();
 
-  // Ends the UtilityProcess. Must be called after StartUtilityProcess() and
-  // before destruction.
-  // TODO(bulach): figure out an appropriate hook so that we can keep the
-  // UtilityProcess running for a longer period of time and avoid spinning it
-  // on every IDBObjectStore::Put call.
-  void EndUtilityProcess();
+  // Shut down the IndexedDBKeyUtilityClient if it was ever started.
+  static void Shutdown();
 
   // Synchronously obtain the |keys| from |values| for the given |key_path|.
   void CreateIDBKeysFromSerializedValuesAndKeyPath(
@@ -57,8 +53,16 @@ class IndexedDBKeyUtilityClient
   };
 
   friend class base::RefCountedThreadSafe<IndexedDBKeyUtilityClient>;
+  IndexedDBKeyUtilityClient();
   ~IndexedDBKeyUtilityClient();
 
+  // Lock to protect the instance_ member.
+  static base::Lock instantiation_lock_;
+  static scoped_refptr<IndexedDBKeyUtilityClient> instance_;

[bulach, 2011/01/14 17:55:08]

iirc, it's not safe / advisable to have non-POD static, and valgrind may
complain about them too..
would it be possible to wrap this all up in base::Singleton instead? (as in,
have a singleton that owns this class, possibly move it to the cc file, and
expose just GetInstance, CreateIDBKeys and Shutdown..)

+
+  // Starts the UtilityProcess. Must be called before any other method.
+  void StartUtilityProcess();
+
   void GetRDHAndStartUtilityProcess();
   void StartUtilityProcessInternal(ResourceDispatcherHost* rdh);
   void EndUtilityProcessInternal();