Strip protocol part when doing 3PID invites for. Partially fixes elem…

…ent-hq/element-web#419

lib/client.js

@@ -1431,8 +1431,21 @@ MatrixClient.prototype.inviteByThreePid = function(roomId, medium, address, call
         { $roomId: roomId }
     );
 
+    var identityServerUrl = this.getIdentityServerUrl();
+    if (!identityServerUrl) {
+        return q.reject(new MatrixError({
+            error: "No supplied identity server URL",
+            errcode: "ORG.MATRIX.JSSDK_MISSING_PARAM"
+        }));
+    }
+    if (identityServerUrl.indexOf("http://") === 0 ||
+            identityServerUrl.indexOf("https://") === 0) {
+        // this request must not have the protocol part because reasons
+        identityServerUrl = identityServerUrl.split("://")[1];
+    }
+
     return this._http.authedRequest(callback, "POST", path, undefined, {
-        id_server: this.getIdentityServerUrl(),
+        id_server: identityServerUrl,
         medium: medium,
         address: address
     });