Revert "Refactor CrashDump*Manager to use a shared CrashDumpObserver singleton."

components/crash/content/browser/crash_micro_dump_manager_android.h

Index: components/crash/content/browser/crash_micro_dump_manager_android.h
diff --git a/components/crash/content/browser/crash_micro_dump_manager_android.h b/components/crash/content/browser/crash_micro_dump_manager_android.h
new file mode 100644
index 0000000000000000000000000000000000000000..753b344030a44bf4864f46e1d0994b30878fdcb8
--- /dev/null
+++ b/components/crash/content/browser/crash_micro_dump_manager_android.h
@@ -0,0 +1,69 @@
+// Copyright 2015 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_CONTENT_BROWSER_CRASH_MICRO_DUMP_MANAGER_ANDROID_H_
+#define COMPONENTS_CRASH_CONTENT_BROWSER_CRASH_MICRO_DUMP_MANAGER_ANDROID_H_
+
+#include <map>
+#include <memory>
+
+#include "base/files/scoped_file.h"
+#include "base/memory/singleton.h"
+#include "base/memory/weak_ptr.h"
+#include "base/process/kill.h"
+#include "base/sync_socket.h"
+#include "base/synchronization/lock.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+namespace breakpad {
+
+// This class manages behavior of the browser on renderer crashes when
+// microdumps are used for capturing the crash stack.  Normally, in this case
+// the browser doesn't need to do much, because a microdump is written into
+// Android log by the renderer process itself.  However, the browser may need to
+// crash itself on a renderer crash.  Since on Android renderers are not child
+// processes of the browser, it can't access the exit code. Instead, the browser
+// uses a dedicated pipe in order to receive the information about the renderer
+// crash status.
+class CrashMicroDumpManager : public content::NotificationObserver {
+ public:
+  // There is only a single instance of CrashMicroDumpManager per browser
+  // process. It needs to be created on the UI thread.
+  static CrashMicroDumpManager* GetInstance();
+
+  // Returns a pipe that should be used to transfer termination cause of
+  // |child_process_id|.
+  base::ScopedFD CreateCrashInfoChannel(int child_process_id);
+
+ private:
+  friend struct base::DefaultSingletonTraits<CrashMicroDumpManager>;
+
+  CrashMicroDumpManager();
+  ~CrashMicroDumpManager() override;
+
+  // NotificationObserver implementation:
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
+
+  // Called on child process exit (including crash).
+  void HandleChildTerminationOnFileThread(
+      int child_process_id,
+      base::TerminationStatus termination_status);
+
+  content::NotificationRegistrar notification_registrar_;
+
+  // This map should only be accessed with its lock aquired as it is accessed
+  // from the PROCESS_LAUNCHER, FILE, and UI threads.
+  base::Lock child_process_id_to_pipe_lock_;
+  std::map<int, std::unique_ptr<base::SyncSocket>> child_process_id_to_pipe_;
+  base::WeakPtrFactory<CrashMicroDumpManager> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(CrashMicroDumpManager);
+};
+
+}  // namespace breakpad
+
+#endif  // COMPONENTS_CRASH_CONTENT_BROWSER_CRASH_MICRO_DUMP_MANAGER_ANDROID_H_