Refactor CrashDump*Manager to use a shared CrashDumpObserver singleton.

components/crash/content/browser/crash_dump_manager_android.h

 // 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_CONTENT_BROWSER_CRASH_DUMP_MANAGER_ANDROID_H_
 #define COMPONENTS_CRASH_CONTENT_BROWSER_CRASH_DUMP_MANAGER_ANDROID_H_
 
 #include <map>
 
-#include "base/android/application_status_listener.h"
-#include "base/files/file.h"
 #include "base/files/file_path.h"
-#include "base/macros.h"
-#include "base/process/kill.h"
-#include "base/process/process.h"
 #include "base/synchronization/lock.h"
-#include "content/public/browser/browser_child_process_observer.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-#include "content/public/common/process_type.h"
+#include "components/crash/content/browser/crash_dump_observer_android.h"
 
 namespace breakpad {
 
 // This class manages the crash minidumps.
 // On Android, because of process isolation, each renderer process runs with a
 // different UID. As a result, we cannot generate the minidumps in the browser
 // (as the browser process does not have access to some system files for the
 // crashed process). So the minidump is generated in the renderer process.
 // Since the isolated process cannot open files, we provide it on creation with
-// a file descriptor where to write the minidump in the event of a crash.
+// a file descriptor into which to write the minidump in the event of a crash.
 // This class creates these file descriptors and associates them with render
-// processes and take the appropriate action when the render process terminates.
-class CrashDumpManager : public content::BrowserChildProcessObserver,
-                         public content::NotificationObserver {
+// processes and takes the appropriate action when the render process
+// terminates.
+class CrashDumpManager : public breakpad::CrashDumpObserver::Client {
  public:
-  // The embedder should create a single instance of the CrashDumpManager.
-  static CrashDumpManager* GetInstance();
-
-  // Should be created on the UI thread.
-  explicit CrashDumpManager(const base::FilePath& crash_dump_dir);
-
+  CrashDumpManager(const base::FilePath& crash_dump_dir, int descriptor_id);
   ~CrashDumpManager() override;
 
-  // Returns a file that should be used to generate a minidump for the process
-  // |child_process_id|.
-  base::File CreateMinidumpFile(int child_process_id);
+  // breakpad::CrashDumpObserver::Client implementation:
+  void OnChildStart(int child_process_id,
+                    content::FileDescriptorInfo* mappings) override;
+  void OnChildExit(int child_process_id,
+                   base::ProcessHandle pid,
+                   content::ProcessType process_type,
+                   base::TerminationStatus termination_status,
+                   base::android::ApplicationState app_state) override;
 
  private:
   typedef std::map<int, base::FilePath> ChildProcessIDToMinidumpPath;
 
   // This enum is used to back a UMA histogram, and must be treated as
   // append-only.
   enum ExitStatus {
     EMPTY_MINIDUMP_WHILE_RUNNING,
     EMPTY_MINIDUMP_WHILE_PAUSED,
     EMPTY_MINIDUMP_WHILE_BACKGROUND,
     VALID_MINIDUMP_WHILE_RUNNING,
     VALID_MINIDUMP_WHILE_PAUSED,
     VALID_MINIDUMP_WHILE_BACKGROUND,
     MINIDUMP_STATUS_COUNT
   };
 
   static void ProcessMinidump(const base::FilePath& minidump_path,
+                              const base::FilePath& crash_dump_dir,
                               base::ProcessHandle pid,
                               content::ProcessType process_type,
                               base::TerminationStatus termination_status,
                               base::android::ApplicationState app_state);
 
-  // content::BrowserChildProcessObserver implementation:
-  void BrowserChildProcessHostDisconnected(
-      const content::ChildProcessData& data) override;
-  void BrowserChildProcessCrashed(
-      const content::ChildProcessData& data,
-      int exit_code) override;
-
-  // NotificationObserver implementation:
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
-  // Called on child process exit (including crash).
-  void OnChildExit(int child_process_id,
-                   base::ProcessHandle pid,
-                   content::ProcessType process_type,
-                   base::TerminationStatus termination_status,
-                   base::android::ApplicationState app_state);
-
-  content::NotificationRegistrar notification_registrar_;
-
   // This map should only be accessed with its lock aquired as it is accessed
   // from the PROCESS_LAUNCHER and UI threads.
   base::Lock child_process_id_to_minidump_path_lock_;
   ChildProcessIDToMinidumpPath child_process_id_to_minidump_path_;
 
+  // The directory in which temporary minidump files should be created.
   base::FilePath crash_dump_dir_;
 
-  static CrashDumpManager* instance_;
+  // The id used to identify the file descriptor in the set of file
+  // descriptor mappings passed to the child process.
+  int descriptor_id_;
 
   DISALLOW_COPY_AND_ASSIGN(CrashDumpManager);
 };
 
 }  // namespace breakpad
 
 #endif  // COMPONENTS_CRASH_CONTENT_BROWSER_CRASH_DUMP_MANAGER_ANDROID_H_