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diff --git a/dom/media/gmp/GMPCrashHelperHolder.h b/dom/media/gmp/GMPCrashHelperHolder.h
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+++ b/dom/media/gmp/GMPCrashHelperHolder.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef GMPCrashHelperHolder_h_
+#define GMPCrashHelperHolder_h_
+
+#include "mozilla/RefPtr.h"
+#include "GMPCrashHelper.h"
+
+namespace mozilla {
+
+// Disconnecting the GMPCrashHelpers at the right time is hard. We need to
+// ensure that in the crashing case that we stay connected until the
+// "gmp-plugin-crashed" message is processed in the content process.
+//
+// We have two channels connecting to the GMP; PGMP which connects from
+// chrome to GMP process, and PGMPContent, which bridges between the content
+// and GMP process. If the GMP crashes both PGMP and PGMPContent receive
+// ActorDestroy messages and begin to shutdown at the same time.
+//
+// However the crash report mini dump must be generated in the chrome
+// process' ActorDestroy, before the "gmp-plugin-crashed" message can be sent
+// to the content process. We fire the "PluginCrashed" event when we handle
+// the "gmp-plugin-crashed" message in the content process, and we need the
+// crash helpers to do that.
+//
+// The PGMPContent's managed actors' ActorDestroy messages are the only shutdown
+// notification we get in the content process, but we can't disconnect the
+// crash handlers there in the crashing case, as ActorDestroy happens before
+// we've received the "gmp-plugin-crashed" message and had a chance for the
+// crash helpers to generate the window to dispatch PluginCrashed to initiate
+// the crash report submission notification box.
+//
+// So we need to ensure that in the content process, the GMPCrashHelpers stay
+// connected to the GMPService until after ActorDestroy messages are received
+// if there's an abnormal shutdown. In the case where the GMP doesn't crash,
+// we do actually want to disconnect GMPCrashHandlers in ActorDestroy, since
+// we don't have any other signal that a GMP actor is shutting down. If we don't
+// disconnect the crash helper there in the normal shutdown case, the helper
+// will stick around forever and leak.
+//
+// In the crashing case, the GMPCrashHelpers are deallocated when the crash
+// report is processed in GeckoMediaPluginService::RunPluginCrashCallbacks().
+//
+// It's a bit yuck that we have to have two paths for disconnecting the crash
+// helpers, but there aren't really any better options.
+class GMPCrashHelperHolder {
+ public:
+  void SetCrashHelper(GMPCrashHelper* aHelper);
+
+  GMPCrashHelper* GetCrashHelper();
+
+  void MaybeDisconnect(bool aAbnormalShutdown);
+
+ private:
+  RefPtr<GMPCrashHelper> mCrashHelper;
+};
+
+}  // namespace mozilla
+
+#endif  // GMPCrashHelperHolder_h_