Reland r290125: Close all active PeerConnections upon OS suspend

This replaces the CHECK with an if statement because the RenderProcessHost
is cleaned up before deletion, which means it can be unregistered from the
list of available RenderProcessHosts before being destructed (hence CHECK
firing).

BUG=403618,404715

Review URL: https://codereview.chromium.org/482333003

Cr-Commit-Position: refs/heads/master@{#290757}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290757 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/media/peer_connection_tracker_host.cc

@@ -3,14 +3,20 @@
 // found in the LICENSE file.
 #include "content/browser/renderer_host/media/peer_connection_tracker_host.h"
 
+#include "base/power_monitor/power_monitor.h"
 #include "content/browser/media/webrtc_internals.h"
 #include "content/common/media/peer_connection_tracker_messages.h"
+#include "content/public/browser/render_process_host.h"
 
 namespace content {
 
 PeerConnectionTrackerHost::PeerConnectionTrackerHost(int render_process_id)
     : BrowserMessageFilter(PeerConnectionTrackerMsgStart),
-      render_process_id_(render_process_id) {}
+      render_process_id_(render_process_id) {
+  base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
+  if (power_monitor)
+    power_monitor->AddObserver(this);
+}
 
 bool PeerConnectionTrackerHost::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
@@ -36,6 +42,9 @@ void PeerConnectionTrackerHost::OverrideThreadForMessage(
 }
 
 PeerConnectionTrackerHost::~PeerConnectionTrackerHost() {
+  base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
+  if (power_monitor)
+    power_monitor->RemoveObserver(this);
 }
 
 void PeerConnectionTrackerHost::OnAddPeerConnection(
@@ -82,4 +91,11 @@ void PeerConnectionTrackerHost::OnGetUserMedia(
                                                  video_constraints);
 }
 
+void PeerConnectionTrackerHost::OnSuspend() {
+  content::RenderProcessHost* host =
+      content::RenderProcessHost::FromID(render_process_id_);
+  if (host)
+    host->Send(new PeerConnectionTracker_OnSuspend());
+}
+
 }  // namespace content

content/browser/renderer_host/media/peer_connection_tracker_host.h

@@ -5,6 +5,7 @@
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_PEER_CONNECTION_TRACKER_HOST_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_PEER_CONNECTION_TRACKER_HOST_H_
 
+#include "base/power_monitor/power_observer.h"
 #include "content/public/browser/browser_message_filter.h"
 
 struct PeerConnectionInfo;
@@ -16,9 +17,11 @@ class ListValue;
 namespace content {
 
 // This class is the host for PeerConnectionTracker in the browser process
-// managed by RenderProcessHostImpl. It passes IPC messages between
-// WebRTCInternals and PeerConnectionTracker.
-class PeerConnectionTrackerHost : public BrowserMessageFilter {
+// managed by RenderProcessHostImpl. It receives PeerConnection events from
+// PeerConnectionTracker as IPC messages that it forwards to WebRTCInternals.
+// It also forwards browser process events to PeerConnectionTracker via IPC.
+class PeerConnectionTrackerHost : public BrowserMessageFilter,
+                                  public base::PowerObserver {
  public:
   PeerConnectionTrackerHost(int render_process_id);
 
@@ -27,6 +30,9 @@ class PeerConnectionTrackerHost : public BrowserMessageFilter {
   virtual void OverrideThreadForMessage(const IPC::Message& message,
                                         BrowserThread::ID* thread) OVERRIDE;
 
+  // base::PowerObserver override.
+  virtual void OnSuspend() OVERRIDE;
+
  protected:
   virtual ~PeerConnectionTrackerHost();
 

content/common/media/peer_connection_tracker_messages.h

@@ -40,3 +40,4 @@ IPC_MESSAGE_CONTROL5(PeerConnectionTrackerHost_GetUserMedia,
 
 // Messages sent to PeerConnectionTracker.
 IPC_MESSAGE_CONTROL0(PeerConnectionTracker_GetAllStats)
+IPC_MESSAGE_CONTROL0(PeerConnectionTracker_OnSuspend)

content/renderer/media/peer_connection_tracker.cc

@@ -278,6 +278,7 @@ bool PeerConnectionTracker::OnControlMessageReceived(
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PeerConnectionTracker, message)
     IPC_MESSAGE_HANDLER(PeerConnectionTracker_GetAllStats, OnGetAllStats)
+    IPC_MESSAGE_HANDLER(PeerConnectionTracker_OnSuspend, OnSuspend)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -297,6 +298,13 @@ void PeerConnectionTracker::OnGetAllStats() {
   }
 }
 
+void PeerConnectionTracker::OnSuspend() {
+  for (PeerConnectionIdMap::iterator it = peer_connection_id_map_.begin();
+       it != peer_connection_id_map_.end(); ++it) {
+    it->first->stop();
+  }
+}
+
 void PeerConnectionTracker::RegisterPeerConnection(
     RTCPeerConnectionHandler* pc_handler,
     const webrtc::PeerConnectionInterface::RTCConfiguration& config,

content/renderer/media/peer_connection_tracker.h

@@ -161,6 +161,9 @@ class CONTENT_EXPORT PeerConnectionTracker : public RenderProcessObserver {
   // IPC Message handler for getting all stats.
   void OnGetAllStats();
 
+  // Called when the browser process reports a suspend event from the OS.
+  void OnSuspend();
+
   void SendPeerConnectionUpdate(RTCPeerConnectionHandler* pc_handler,
                                 const std::string& callback_type,
                                 const std::string& value);