Fix race condition for non-open/create operations happening after a doom.

net/disk_cache/simple/simple_synchronous_entry.h

 // Copyright (c) 2013 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.
 
 #ifndef NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_
 
 #include <algorithm>
 #include <string>
 #include <utility>
@@ skipping 67 matching lines @@
                         bool had_index,
                         SimpleEntryCreationResults* out_results);
 
   static void CreateEntry(net::CacheType cache_type,
                           const base::FilePath& path,
                           const std::string& key,
                           uint64 entry_hash,
                           bool had_index,
                           SimpleEntryCreationResults* out_results);
 
-  // Deletes an entry without first Opening it. Does not check if there is
-  // already an Entry object in memory holding the open files. Be careful! This
-  // is meant to be used by the Backend::DoomEntry() call. |callback| will be
-  // run by |callback_runner|.
-  static void DoomEntry(const base::FilePath& path,
-                        const std::string& key,
-                        uint64 entry_hash,
-                        int* out_result);
+  // Deletes an entry from the file system without affecting the state of the
+  // corresponding instance, if any (allowing operations to continue to be
+  // executed through that instance). Returns a net error code.
+  static int DoomEntry(const base::FilePath& path,
+                       const std::string& key,
+                       uint64 entry_hash);
 
   // Like |DoomEntry()| above. Deletes all entries corresponding to the
   // |key_hashes|. Succeeds only when all entries are deleted. Returns a net
   // error code.
   static int DoomEntrySet(scoped_ptr<std::vector<uint64> > key_hashes,
                           const base::FilePath& path);
 
   // N.B. ReadData(), WriteData(), CheckEOFRecord() and Close() may block on IO.
   void ReadData(const EntryOperationData& in_entry_op,
                 net::IOBuffer* out_buf,
@@ skipping 56 matching lines @@
 
   bool have_open_files_;
   bool initialized_;
 
   base::PlatformFile files_[kSimpleEntryFileCount];
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_