Revert "Add thread checker to PortAllocator and its subclasses and fix a bug"

This reverts commit fc43d11717e16dd427ac84fee614e5511e43cefd.

Reason for revert: Crashes downstream tests

Original change's description:
> Add thread checker to PortAllocator and its subclasses and fix a bug
> causing memory contention by threads.
> 
> PortAllocator and its subclasses assume all of their methods except the
> constructor must be called on the same thread (the network thread in
> practice). This CL adds a thread checker to PortAllocator and its
> subclasses for thread safety, and fixes bugs of invoking some of their
> methods in PeerConnection on the signaling thread.
> 
> Bug: webrtc:9112
> Change-Id: I33ba9bae72ec09a45ec70435962f3f25cd31583c
> Reviewed-on: https://webrtc-review.googlesource.com/66945
> Commit-Queue: Qingsi Wang <qingsi@google.com>
> Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#22814}

TBR=deadbeef@webrtc.org,pthatcher@google.com,pthatcher@webrtc.org,qingsi@google.com,honghaiz@webrtc.org

Change-Id: I2db6561d5d6366d38caa58c3e719d0d48eda70c2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:9112
Reviewed-on: https://webrtc-review.googlesource.com/69200
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Patrik Höglund <phoglund@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22818}
diff --git a/p2p/client/basicportallocator_unittest.cc b/p2p/client/basicportallocator_unittest.cc
index 6ed13b5..f39e61e 100644
--- a/p2p/client/basicportallocator_unittest.cc
+++ b/p2p/client/basicportallocator_unittest.cc
@@ -166,7 +166,6 @@
     allocator_.reset(new BasicPortAllocator(&network_manager_, stun_servers,
                                             kRelayUdpIntAddr, kRelayTcpIntAddr,
                                             kRelaySslTcpIntAddr));
-    allocator_->Initialize();
     allocator_->set_step_delay(kMinimumStepDelay);
   }
 
@@ -202,7 +201,6 @@
   // Endpoint is on the public network. No STUN or TURN.
   void ResetWithNoServersOrNat() {
     allocator_.reset(new BasicPortAllocator(&network_manager_));
-    allocator_->Initialize();
     allocator_->set_step_delay(kMinimumStepDelay);
   }
   // Endpoint is behind a NAT, with STUN specified.
@@ -485,8 +483,7 @@
     }
     allocator_.reset(new BasicPortAllocator(
         &network_manager_, nat_socket_factory_.get(), stun_servers));
-    allocator_->Initialize();
-    allocator_->set_step_delay(kMinimumStepDelay);
+    allocator().set_step_delay(kMinimumStepDelay);
   }
 
   std::unique_ptr<rtc::VirtualSocketServer> vss_;
@@ -582,7 +579,6 @@
     AddInterface(kClientAddr, "net1");
     AddInterface(kClientIPv6Addr, "net1");
     allocator_.reset(new BasicPortAllocator(&network_manager_));
-    allocator_->Initialize();
     allocator_->SetConfiguration(allocator_->stun_servers(),
                                  allocator_->turn_servers(), 0, true);
     AddTurnServers(kTurnUdpIntIPv6Addr, rtc::SocketAddress());
@@ -620,7 +616,6 @@
     turn_server_.AddInternalSocket(kTurnTcpIntAddr, PROTO_TCP);
     AddInterface(kClientAddr);
     allocator_.reset(new BasicPortAllocator(&network_manager_));
-    allocator_->Initialize();
     allocator_->SetConfiguration(allocator_->stun_servers(),
                                  allocator_->turn_servers(), 0, true);
     AddTurnServers(kTurnUdpIntAddr, kTurnTcpIntAddr);
@@ -667,7 +662,6 @@
     AddInterface(kClientAddr2, "net2", rtc::ADAPTER_TYPE_CELLULAR);
     AddInterface(kClientIPv6Addr2, "net2", rtc::ADAPTER_TYPE_CELLULAR);
     allocator_.reset(new BasicPortAllocator(&network_manager_));
-    allocator_->Initialize();
     allocator_->SetConfiguration(allocator_->stun_servers(),
                                  allocator_->turn_servers(), 0, true);
     // Have both UDP/TCP and IPv4/IPv6 TURN ports.
@@ -1657,7 +1651,6 @@
   turn_server_.AddInternalSocket(kTurnTcpIntAddr, PROTO_TCP);
   AddInterface(kClientAddr);
   allocator_.reset(new BasicPortAllocator(&network_manager_));
-  allocator_->Initialize();
 
   AddTurnServers(kTurnUdpIntAddr, kTurnTcpIntAddr);
 
@@ -1762,7 +1755,6 @@
                                  PROTO_UDP);
   AddInterface(kClientAddr);
   allocator_.reset(new BasicPortAllocator(&network_manager_));
-  allocator_->Initialize();
   RelayServerConfig turn_server(RELAY_TURN);
   RelayCredentials credentials(kTurnUsername, kTurnPassword);
   turn_server.credentials = credentials;