Revert of Stop all PeerConnections upon suspend from Blink side (patchset #3...

Revert of Stop all PeerConnections upon suspend from Blink side (patchset #3 of https://codereview.chromium.org/475263002/)

Reason for revert:
Causing browser crashes due to race, BUG=404767.

Original issue's description:
> Stop all PeerConnections upon suspend from Blink side
>
> BUG=403618
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=291213

TBR=jiayl@chromium.org,vrk@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=403618

Review URL: https://codereview.chromium.org/482443003

Cr-Commit-Position: refs/heads/master@{#291778}

content/renderer/media/peer_connection_tracker.cc

@@ -301,7 +301,7 @@ void PeerConnectionTracker::OnGetAllStats() {
 void PeerConnectionTracker::OnSuspend() {
   for (PeerConnectionIdMap::iterator it = peer_connection_id_map_.begin();
        it != peer_connection_id_map_.end(); ++it) {
-    it->first->CloseClientPeerConnection();
+    it->first->stop();
   }
 }
 

content/renderer/media/rtc_peer_connection_handler.cc

@@ -781,10 +781,6 @@ void RTCPeerConnectionHandler::GetStats(
   }
 }
 
-void RTCPeerConnectionHandler::CloseClientPeerConnection() {
-  client_->closePeerConnection();
-}
-
 blink::WebRTCDataChannelHandler* RTCPeerConnectionHandler::createDataChannel(
     const blink::WebString& label, const blink::WebRTCDataChannelInit& init) {
   DVLOG(1) << "createDataChannel label " << base::UTF16ToUTF8(label);

content/renderer/media/rtc_peer_connection_handler.h

@@ -185,9 +185,6 @@ class CONTENT_EXPORT RTCPeerConnectionHandler
                 webrtc::MediaStreamTrackInterface* track,
                 webrtc::PeerConnectionInterface::StatsOutputLevel level);
 
-  // Tells the |client_| to close RTCPeerConnection.
-  void CloseClientPeerConnection();
-
   PeerConnectionTracker* peer_connection_tracker();
 
  protected: