indexeddb: Removed use of dangling ptr in writeBlobToFileOnIOThread.

content/browser/indexed_db/indexed_db_active_blob_registry_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <set>
 
 #include "base/test/test_simple_task_runner.h"
 #include "content/browser/indexed_db/indexed_db_active_blob_registry.h"
 #include "content/browser/indexed_db/indexed_db_backing_store.h"
 #include "content/browser/indexed_db/indexed_db_factory_impl.h"
@@ skipping 37 matching lines @@
 
  private:
   std::set<GURL> origins_;
   bool duplicate_calls_;
 
   DISALLOW_COPY_AND_ASSIGN(MockIDBFactory);
 };
 
 class MockIDBBackingStore : public IndexedDBFakeBackingStore {
  public:
-  MockIDBBackingStore(IndexedDBFactory* factory, base::TaskRunner* task_runner)
+  MockIDBBackingStore(IndexedDBFactory* factory,
+                      base::SequencedTaskRunner* task_runner)
       : IndexedDBFakeBackingStore(factory, task_runner),
         duplicate_calls_(false) {}
 
   virtual void ReportBlobUnused(int64 database_id, int64 blob_key) OVERRIDE {
     unused_blobs_.insert(std::make_pair(database_id, blob_key));
   }
 
   typedef std::pair<int64, int64> KeyPair;
   typedef std::set<KeyPair> KeyPairSet;
   bool CheckUnusedBlobsEmpty() const {
@@ skipping 196 matching lines @@
   RunUntilIdle();
 
   // Nothing changes.
   EXPECT_TRUE(factory()->CheckSingleOriginInUse(backing_store()->origin_url()));
   EXPECT_TRUE(backing_store()->CheckUnusedBlobsEmpty());
 }
 
 }  // namespace
 
 }  // namespace content