Identify the hung thread using the Wait Chain Traversal API

chrome/chrome_watcher/wait_chain_util_win.h

Index: chrome/chrome_watcher/wait_chain_util_win.h
diff --git a/chrome/chrome_watcher/wait_chain_util_win.h b/chrome/chrome_watcher/wait_chain_util_win.h
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+// Copyright 2016 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 CHROME_CHROME_WATCHER_WAIT_CHAIN_UTIL_WIN_H_
+#define CHROME_CHROME_WATCHER_WAIT_CHAIN_UTIL_WIN_H_
+
+#include <windows.h>
+#include <wct.h>
+
+#include <vector>
+
+// Get the wait chain for the |thread_id|. Also specifies if the |wait_chain|
+// contains a deadlock. Returns true on success.
+//
+// From MSDN: A wait chain is an alternating sequence of threads and
+// synchronization objects; each thread waits for the object that follows it,
+// which is owned by the subsequent thread in the chain.
+bool GetThreadWaitChain(DWORD thread_id,
+                        std::vector<WAITCHAIN_NODE_INFO>* wait_chain,
+                        bool* is_deadlock);
+
+// Returns a string that represents the node for a wait chain.
+std::wstring WaitChainNodeToString(const WAITCHAIN_NODE_INFO& node);
+
+#endif  // CHROME_CHROME_WATCHER_WAIT_CHAIN_UTIL_WIN_H_