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

net/disk_cache/simple/simple_synchronous_entry.cc

Index: net/disk_cache/simple/simple_synchronous_entry.cc
diff --git a/net/disk_cache/simple/simple_synchronous_entry.cc b/net/disk_cache/simple/simple_synchronous_entry.cc
index 54526247e9196697d82a23c5550bb19b76e11acf..eddd115c97a2504ed9bbe0ee0559346743236f05 100644
--- a/net/disk_cache/simple/simple_synchronous_entry.cc
+++ b/net/disk_cache/simple/simple_synchronous_entry.cc
@@ -246,14 +246,13 @@ bool SimpleSynchronousEntry::DeleteFilesForEntryHash(
 }
 
 // static
-void SimpleSynchronousEntry::DoomEntry(
+int SimpleSynchronousEntry::DoomEntry(
     const FilePath& path,
     const std::string& key,
-    uint64 entry_hash,
-    int* out_result) {
+    uint64 entry_hash) {
   DCHECK_EQ(entry_hash, GetEntryHashKey(key));
-  bool deleted_well = DeleteFilesForEntryHash(path, entry_hash);
-  *out_result = deleted_well ? net::OK : net::ERR_FAILED;
+  const bool deleted_well = DeleteFilesForEntryHash(path, entry_hash);
+  return deleted_well ? net::OK : net::ERR_FAILED;
 }
 
 // static