Revert of Turn components/crash into a layered component.

components/crash/browser/crash_handler_host_linux.h

Index: components/crash/browser/crash_handler_host_linux.h
diff --git a/components/crash/browser/crash_handler_host_linux.h b/components/crash/browser/crash_handler_host_linux.h
new file mode 100644
index 0000000000000000000000000000000000000000..876a0a5eb13e37d4548f8574a29113c5bac8181d
--- /dev/null
+++ b/components/crash/browser/crash_handler_host_linux.h
@@ -0,0 +1,93 @@
+// Copyright 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 COMPONENTS_CRASH_BROWSER_CRASH_HANDLER_HOST_LINUX_H_
+#define COMPONENTS_CRASH_BROWSER_CRASH_HANDLER_HOST_LINUX_H_
+
+#include <sys/types.h>
+
+#include <string>
+
+#include "base/compiler_specific.h"
+#include "base/files/file_path.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "base/threading/sequenced_worker_pool.h"
+
+namespace base {
+class Thread;
+}
+
+namespace breakpad {
+
+struct BreakpadInfo;
+
+// This is the host for processes which run breakpad inside the sandbox on
+// Linux or Android. We perform the crash dump from the browser because it
+// allows us to be outside the sandbox.
+//
+// Processes signal that they need to be dumped by sending a datagram over a
+// UNIX domain socket. All processes of the same type share the client end of
+// this socket which is installed in their descriptor table before exec.
+class CrashHandlerHostLinux : public base::MessageLoopForIO::Watcher,
+                              public base::MessageLoop::DestructionObserver {
+ public:
+  CrashHandlerHostLinux(const std::string& process_type,
+                        const base::FilePath& dumps_path,
+                        bool upload);
+  ~CrashHandlerHostLinux() override;
+
+  // Starts the uploader thread. Must be called immediately after creating the
+  // class.
+  void StartUploaderThread();
+
+  // Get the file descriptor which processes should be given in order to signal
+  // crashes to the browser.
+  int GetDeathSignalSocket() const {
+    return process_socket_;
+  }
+
+  // MessagePumbLibevent::Watcher impl:
+  void OnFileCanWriteWithoutBlocking(int fd) override;
+  void OnFileCanReadWithoutBlocking(int fd) override;
+
+  // MessageLoop::DestructionObserver impl:
+  void WillDestroyCurrentMessageLoop() override;
+
+  // Whether we are shutting down or not.
+  bool IsShuttingDown() const;
+
+ private:
+  void Init();
+
+  // Do work in a sequenced worker pool for OnFileCanReadWithoutBlocking().
+  void WriteDumpFile(scoped_ptr<BreakpadInfo> info,
+                     scoped_ptr<char[]> crash_context,
+                     pid_t crashing_pid,
+                     int signal_fd);
+
+  // Continue OnFileCanReadWithoutBlocking()'s work on the IO thread.
+  void QueueCrashDumpTask(scoped_ptr<BreakpadInfo> info, int signal_fd);
+
+  std::string process_type_;
+  base::FilePath dumps_path_;
+  bool upload_;
+
+  int process_socket_;
+  int browser_socket_;
+
+  base::MessageLoopForIO::FileDescriptorWatcher file_descriptor_watcher_;
+  scoped_ptr<base::Thread> uploader_thread_;
+  bool shutting_down_;
+
+  // Unique sequence token so that writing crash dump won't be blocked
+  // by other tasks.
+  base::SequencedWorkerPool::SequenceToken worker_pool_token_;
+
+  DISALLOW_COPY_AND_ASSIGN(CrashHandlerHostLinux);
+};
+
+}  // namespace breakpad
+
+#endif  // COMPONENTS_CRASH_BROWSER_CRASH_HANDLER_HOST_LINUX_H_