Move video call message state and duration to head.

'webrtc' header for state.
'webrtc-duration' header for duration.

Content is now Drafty.videoCall() / VC.

src/views/messages-view.jsx

@@ -1137,20 +1137,14 @@ class MessagesView extends React.Component {
               );
               prevDate = thisDate;
             }
-            let duration;
-            if (msg.head && isVideoCall(msg.head.mime)) {
-              topic.messageVersions(msg, (cur, before) => {
-                if (cur.content == 'finished' && before.content == 'accepted') {
-                  duration = msg.ts - before.ts;
-                }
-              });
-            }
+            const duration = msg.head ? msg.head['webrtc-duration'] : undefined;
             messageNodes.push(
               <ChatMessage
                 tinode={this.props.tinode}
                 content={msg.content}
                 mimeType={msg.head ? msg.head.mime : null}
                 timestamp={msg.ts}
+                callState={msg.head ? msg.head.webrtc : null}
                 duration={duration}
                 response={isReply}
                 seq={msg.seq}

src/views/tinode-web.jsx

@@ -21,7 +21,7 @@ import { API_KEY, APP_NAME, DEFAULT_P2P_ACCESS_MODE, FORWARDED_PREVIEW_LENGTH, L
   MEDIA_BREAKPOINT, RECEIVED_DELAY } from '../config.js';
 import { CALL_STATE_NONE, CALL_STATE_OUTGOING_INITATED,
          CALL_STATE_INCOMING_RECEIVED, CALL_STATE_IN_PROGRESS,
-         CALL_MESSAGE_MIME_TYPE }  from '../constants.js';
+         CALL_MESSAGE_MIME_TYPE, CALL_HEAD_STARTED }  from '../constants.js';
 import { PACKAGE_VERSION } from '../version.js';
 import { base64ReEncode, makeImageUrl } from '../lib/blob-helpers.js';
 import { detectServerAddress, isLocalHost, isSecureConnection } from '../lib/host-name.js';
@@ -1687,8 +1687,11 @@ class TinodeWeb extends React.Component {
   handleCallInvite(callTopic, callSeq, callState) {
     switch (callState) {
       case CALL_STATE_OUTGOING_INITATED:
-        let head = {mime: CALL_MESSAGE_MIME_TYPE };
-        this.handleSendMessage('started', undefined, undefined, head)
+        let head = {
+          mime: CALL_MESSAGE_MIME_TYPE,
+          webrtc: CALL_HEAD_STARTED
+        };
+        this.handleSendMessage(Drafty.videoCall(), undefined, undefined, head)
           .then((ctrl) => {
             if (ctrl.code < 200 || ctrl.code >= 300 || !ctrl.params || !ctrl.params.seq) {
               this.handleCallClose();