Reland of landing: Implement RTCConfiguration.iceCandidatePoolSize.

webrtc/api/peerconnection.h

Index: webrtc/api/peerconnection.h
diff --git a/webrtc/api/peerconnection.h b/webrtc/api/peerconnection.h
index 862c6fb63039eb4478533c1db6e7bea8a870d2c8..15ecc3f4cdac4571ca879cb8ea006192323b62d9 100644
--- a/webrtc/api/peerconnection.h
+++ b/webrtc/api/peerconnection.h
@@ -131,7 +131,7 @@
   void SetRemoteDescription(SetSessionDescriptionObserver* observer,
                             SessionDescriptionInterface* desc) override;
   bool SetConfiguration(
-      const PeerConnectionInterface::RTCConfiguration& config) override;
+      const PeerConnectionInterface::RTCConfiguration& configuration) override;
   bool AddIceCandidate(const IceCandidateInterface* candidate) override;
   bool RemoveIceCandidates(
       const std::vector<cricket::Candidate>& candidates) override;
@@ -210,6 +210,8 @@
     return factory_->signaling_thread();
   }
 
+  rtc::Thread* worker_thread() const { return factory_->worker_thread(); }
+
   void PostSetSessionDescriptionFailure(SetSessionDescriptionObserver* observer,
                                         const std::string& error);
   void PostCreateSessionDescriptionFailure(
@@ -350,6 +352,12 @@
   // Returns the specified SCTP DataChannel in sctp_data_channels_,
   // or nullptr if not found.
   DataChannel* FindDataChannelBySid(int sid) const;
+
+  // Called when first configuring the port allocator.
+  bool InitializePortAllocator_w(const RTCConfiguration& configuration);
+  // Called when SetConfiguration is called. Only a subset of the configuration
+  // is applied.
+  bool ReconfigurePortAllocator_w(const RTCConfiguration& configuration);
 
   // Storing the factory as a scoped reference pointer ensures that the memory
   // in the PeerConnectionFactoryImpl remains available as long as the
@@ -397,11 +405,7 @@
   std::vector<rtc::scoped_refptr<RtpSenderInterface>> senders_;
   std::vector<rtc::scoped_refptr<RtpReceiverInterface>> receivers_;
 
-  // The session_ unique_ptr is declared at the bottom of PeerConnection
-  // because its destruction fires signals (such as VoiceChannelDestroyed)
-  // which will trigger some final actions in PeerConnection...
   std::unique_ptr<WebRtcSession> session_;
-  // ... But stats_ depends on session_ so it should be destroyed even earlier.
   std::unique_ptr<StatsCollector> stats_;
 };