[IndexedDB] Refactoring to remove ref ptrs and host transaction ids.

content/browser/indexed_db/indexed_db_backing_store.h

Index: content/browser/indexed_db/indexed_db_backing_store.h
diff --git a/content/browser/indexed_db/indexed_db_backing_store.h b/content/browser/indexed_db/indexed_db_backing_store.h
index 00d6678f6df333b87daeb6b430f7466b5d0740c3..46d8591a02448e9bc34d096563aad708da04ceca 100644
--- a/content/browser/indexed_db/indexed_db_backing_store.h
+++ b/content/browser/indexed_db/indexed_db_backing_store.h
@@ -19,6 +19,7 @@
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "base/strings/string_piece.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
@@ -90,9 +91,13 @@ class CONTENT_EXPORT IndexedDBBackingStore
     DISALLOW_COPY_AND_ASSIGN(RecordIdentifier);
   };
 
+  enum class BlobWriteResult { FAILURE_ASYNC, SUCCESS_ASYNC, SUCCESS_SYNC };
+
   class BlobWriteCallback : public base::RefCounted<BlobWriteCallback> {
    public:
-    virtual void Run(bool succeeded) = 0;
+    // TODO(dmurph): Make all calls to this method async after measuring
+    // performance.
+    virtual leveldb::Status Run(BlobWriteResult result) = 0;
 
    protected:
     friend class base::RefCounted<BlobWriteCallback>;
@@ -282,6 +287,8 @@ class CONTENT_EXPORT IndexedDBBackingStore
     // has been bumped, and journal cleaning should be deferred.
     bool committing_;
 
+    base::WeakPtrFactory<Transaction> ptr_factory_;
+
     DISALLOW_COPY_AND_ASSIGN(Transaction);
   };