Enable generation of local host candidate.

Source/modules/mediastream/RTCPeerConnection.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 85 matching lines @@
             iceTransports = RTCIceTransportsNone;
         } else if (iceTransportsString == "relay") {
             iceTransports = RTCIceTransportsRelay;
         } else if (iceTransportsString != "all") {
             exceptionState.throwTypeError("Malformed RTCIceTransports");
             return 0;
         }
     }
 
     ArrayValue iceServers;
+    size_t numberOfServers = 0;
+    bool createIceServerArray = true;
     bool ok = DictionaryHelper::get(configuration, "iceServers", iceServers);
-    if (!ok || iceServers.isUndefinedOrNull()) {
-        exceptionState.throwTypeError("Malformed RTCConfiguration");
-        return 0;
-    }
-
-    size_t numberOfServers;
-    ok = iceServers.length(numberOfServers);
     if (!ok) {
-        exceptionState.throwTypeError("Malformed RTCConfiguration");
-        return 0;
+        v8::Local<v8::Value> iceServersValue;
+        // Failed to parse iceServers as ArrayValue, try it as a scalar.
+        ok = DictionaryHelper::get(configuration, "iceServers", iceServersValue);
+        if (!ok || iceServersValue->IsUndefined()) {
+            // if iceServers is not specified (|ok| is false) or specified as
+            // "undefined", treat it as the special case which RTCIceServerArray
+            // will not be created.
+            createIceServerArray = false;
+        } else {
+            exceptionState.throwTypeError("Malformed RTCConfiguration");
+            return 0;
+        }
+    } else {
+        ok = iceServers.length(numberOfServers);
+        if (!ok) {

[tommi (sloooow) - chröme, 2015/09/16 06:19:27]

do we need to handle numberOfServers == 0? (looks like that wasn't done before,
so this might be OK as is, but I'm wondering if you need both numberOfServers
and createIceServerArray or if one of them is enough)

[guoweis_left_chromium, 2015/09/16 17:29:05]

numberOfServers == 0, i.e. iceServers:[], is treated as a way to not cause local
host candidate generated.

[tommi (sloooow) - chröme, 2015/09/16 18:19:45]

ok, but whenever numberOfServers is 0, won't (or should) createIceServerArray be
false?  (and when it's != 0, then createIceServerArray will be true).  Not a big
issue, I'm just wondering if we need two variables for this.

[guoweis_left_chromium, 2015/09/16 22:10:20]

when there is no iceServers specified (or undefined), we want
createiceServerArray to be false. When there is iceServers, we want it to be
true. However, when we do have iceServers but the length is 0, (iceServers:[]),
we still want createiceServerArray to true. I think we still need 2 variables.

+            exceptionState.throwTypeError("Malformed RTCConfiguration");
+            return 0;
+        }
     }

[pthatcher2, 2015/09/16 04:09:58]

Can you put the early returns first?

if (DictionaryHelper::get(configuration, "iceServers", iceServers)) {
  ok = iceServers.length(numberOfServers)
  if (!ok) {
    exceptionState.throwTypeError("Malformed RTCConfiguration");
    return 0;
  )
} else {
  v8::Local<v8::Value> iceServersValue;
  ok = (!DictionaryHelper::get(configuration, "iceServers", iceServersValue)
           || iceServersValue->IsUndefined()); 
  if (!ok) {
    exceptionState.throwTypeError("Malformed RTCConfiguration");
    return 0;    
  }
  createIceServerArray = false;
}

[guoweis_left_chromium, 2015/09/16 17:29:05]

Done.

 
     RTCBundlePolicy bundlePolicy = RTCBundlePolicyBalanced;
     String bundlePolicyString;
     if (DictionaryHelper::get(configuration, "bundlePolicy", bundlePolicyString)) {
         if (bundlePolicyString == "max-compat") {
             bundlePolicy = RTCBundlePolicyMaxCompat;
         } else if (bundlePolicyString == "max-bundle") {
             bundlePolicy = RTCBundlePolicyMaxBundle;
         } else if (bundlePolicyString != "balanced") {
             exceptionState.throwTypeError("Malformed RTCBundlePolicy");
             return 0;
         }
     }
 
     RTCRtcpMuxPolicy rtcpMuxPolicy = RTCRtcpMuxPolicyNegotiate;
     String rtcpMuxPolicyString;
     if (DictionaryHelper::get(configuration, "rtcpMuxPolicy", rtcpMuxPolicyString)) {
         if (rtcpMuxPolicyString == "require") {
             rtcpMuxPolicy = RTCRtcpMuxPolicyRequire;
         } else if (rtcpMuxPolicyString != "negotiate") {
             exceptionState.throwTypeError("Malformed RTCRtcpMuxPolicy");
             return 0;
         }
     }
 
     RTCConfiguration* rtcConfiguration = RTCConfiguration::create();
     rtcConfiguration->setIceTransports(iceTransports);
     rtcConfiguration->setBundlePolicy(bundlePolicy);
     rtcConfiguration->setRtcpMuxPolicy(rtcpMuxPolicy);
+    if (createIceServerArray) {
+        rtcConfiguration->setIceServers(RTCIceServerArray::create());
+    }
 
     for (size_t i = 0; i < numberOfServers; ++i) {
         Dictionary iceServer;
         ok = iceServers.get(i, iceServer);
         if (!ok) {
             exceptionState.throwTypeError("Malformed RTCIceServer");
             return 0;
         }
 
         Vector<String> names;
@@ skipping 27 matching lines @@
         DictionaryHelper::get(iceServer, "username", username);
         DictionaryHelper::get(iceServer, "credential", credential);
 
         for (Vector<String>::iterator iter = urlStrings.begin(); iter != urlStrings.end(); ++iter) {
             KURL url(KURL(), *iter);
             if (!url.isValid() || !(url.protocolIs("turn") || url.protocolIs("turns") || url.protocolIs("stun"))) {
                 exceptionState.throwTypeError("Malformed URL");
                 return 0;
             }
 
-            rtcConfiguration->appendServer(RTCIceServer::create(url, username, credential));
+            rtcConfiguration->iceServers()->appendServer(RTCIceServer::create(url, username, credential));
         }
     }
 
     return rtcConfiguration;
 }
 
 RTCOfferOptions* RTCPeerConnection::parseOfferOptions(const Dictionary& options, ExceptionState& exceptionState)
 {
     if (options.isUndefinedOrNull())
         return 0;
@@ skipping 630 matching lines @@
 {
     visitor->trace(m_localStreams);
     visitor->trace(m_remoteStreams);
     visitor->trace(m_dataChannels);
     visitor->trace(m_scheduledEvents);
     RefCountedGarbageCollectedEventTargetWithInlineData<RTCPeerConnection>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink