fix(SDP<->Jingle): Reject m-line with port 0 only when a=bundle-only is not present

Use unique session id per TPC.
Translate a=rid to Jingle only when simulcast through RIDs, i.e., ssrc-less simulcast is supported

modules/browser/BrowserCapabilities.js

@@ -216,6 +216,15 @@ export default class BrowserCapabilities extends BrowserDetection {
         return !this.usesUnifiedPlan();
     }
 
+    /**
+     * Checks if the browser uses SDP munging for turning on simulcast.
+     *
+     * @returns {boolean}
+     */
+    usesSdpMungingForSimulcast() {
+        return this.isChromiumBased() || this.isSafariWithVP8();
+    }
+
     /**
      * Checks if the browser uses unified plan.
      *
@@ -270,7 +279,15 @@ export default class BrowserCapabilities extends BrowserDetection {
      * @returns {boolean}
      */
     usesAdapter() {
-        return this.usesNewGumFlow();
+        return !this.isFirefox() && !this.isReactNative();
+    }
+
+    /**
+     * Checks if the browser uses RIDs/MIDs for siganling the simulcast streams
+     * to the bridge instead of the ssrcs.
+     */
+    usesRidsForSimulcast() {
+        return false;
     }
 
     /**

modules/xmpp/SDP.js

@@ -1,5 +1,6 @@
 /* global $ */
 
+import browser from '../browser';
 import SDPUtil from './SDPUtil';
 
 /**
@@ -318,7 +319,7 @@ SDP.prototype.toJingle = function(elem, thecreator) {
 
             const ridLines = SDPUtil.findLines(this.media[i], 'a=rid');
 
-            if (ridLines.length) {
+            if (ridLines.length && browser.usesRidsForSimulcast()) {
                 // Map a line which looks like "a=rid:2 send" to just
                 // the rid ("2")
                 const rids = ridLines
@@ -406,7 +407,10 @@ SDP.prototype.toJingle = function(elem, thecreator) {
         } else if (SDPUtil.findLine(m, 'a=inactive', this.session)) {
             elem.attrs({ senders: 'none' });
         }
-        if (mline.port === '0') {
+
+        // Reject an m-line only when port is 0 and a=bundle-only is not present in the section.
+        // The port is automatically set to 0 when bundle-only is used.
+        if (mline.port === '0' && !SDPUtil.findLine(m, 'a=bundle-only', this.session)) {
             // estos hack to reject an m-line
             elem.attrs({ senders: 'rejected' });
         }
@@ -566,9 +570,11 @@ SDP.prototype.rtcpFbFromJingle = function(elem, payloadtype) { // XEP-0293
 // construct an SDP from a jingle stanza
 SDP.prototype.fromJingle = function(jingle) {
     const self = this;
+    const sessionId = (new Date()).getTime();
 
+    // Use a unique session id for every TPC.
     this.raw = 'v=0\r\n'
-        + 'o=- 1923518516 2 IN IP4 0.0.0.0\r\n'// FIXME
+        + `o=- ${sessionId} 2 IN IP4 0.0.0.0\r\n`
         + 's=-\r\n'
         + 't=0 0\r\n';