Remove unused util/thread_event_info.h

Summary:
Remove unused util/thread_event_info.h, which is replaced by
util/thread_operation.h

Test Plan:
make dbg -j32
make release -j32

util/thread_event_info.h

@@ -1,71 +0,0 @@
-// Copyright (c) 2013, Facebook, Inc.  All rights reserved.
-// This source code is licensed under the BSD-style license found in the
-// LICENSE file in the root directory of this source tree. An additional grant
-// of patent rights can be found in the PATENTS file in the same directory.
-//
-// This file defines the structures for thread event and operation.
-// Thread events are used to describe high level action of a
-// thread such as doing compaction or flush, while thread operation
-// are used to describe lower-level action such as reading /
-// writing a file or waiting for a mutex.  Events and operations
-// are designed to be independent.  Typically, a thread usually involves
-// in one event and one operation at any specific point in time.
-
-#pragma once
-
-#include "include/rocksdb/thread_status.h"
-
-#include <string>
-
-namespace rocksdb {
-
-#if ROCKSDB_USING_THREAD_STATUS
-
-// The structure that describes a major thread event.
-struct EventInfo {
-  const ThreadStatus::EventType code;
-  const std::string name;
-};
-
-// The global event table.
-//
-// When updating a status of a thread, the pointer of the EventInfo
-// of the current ThreadStatusData will be pointing to one of the
-// rows in this global table.
-//
-// Note that it's not designed to be constant as in the future we
-// might consider adding global count to the EventInfo.
-static EventInfo global_event_table[] = {
-  {ThreadStatus::EVENT_UNKNOWN, ""},
-  {ThreadStatus::EVENT_COMPACTION, "Compaction"},
-  {ThreadStatus::EVENT_FLUSH, "Flush"}
-};
-
-// The structure that describes a operation.
-struct OperationInfo {
-  const ThreadStatus::OperationType code;
-  const std::string name;
-};
-
-// The global operation table.
-//
-// When updating a status of a thread, the pointer of the OperationInfo
-// of the current ThreadStatusData will be pointing to one of the
-// rows in this global table.
-static OperationInfo global_operation_table[] = {
-  {ThreadStatus::OPERATION_UNKNOWN, ""},
-  {ThreadStatus::OPERATION_WRITE_FILE, "Writing SST file"},
-  {ThreadStatus::OPERATION_READ_FILE, "Reaing SST file"},
-  {ThreadStatus::OPERATION_WAIT_DB_MUTEX, "Waiting DB Mutex"}
-};
-
-#else
-
-struct EventInfo {
-};
-
-struct OperationInfo {
-};
-
-#endif  // ROCKSDB_USING_THREAD_STATUS
-}  // namespace rocksdb