Re-use open popup when requesting a new session

ext/src/shim/cast/index.js

@@ -126,12 +126,21 @@ cast.requestSession = (
         return;
     }
 
+    // Already requesting session
+    if (state.sessionRequestInProgress) {
+        errorCallback(new Error_(ErrorCode.INVALID_PARAMETER
+              , "Session request already in progress."));
+        return;
+    }
+
     // No available receivers
     if (!state.receiverList.length) {
         errorCallback(new Error_(ErrorCode.RECEIVER_UNAVAILABLE));
         return;
     }
 
+    state.sessionRequestInProgress = true;
+
     sessionSuccessCallback = successCallback;
     sessionErrorCallback = errorCallback;
 
@@ -218,6 +227,7 @@ onMessage(message => {
                     });
 
                     state.apiConfig.sessionListener(session);
+                    state.sessionRequestInProgress = false;
                     sessionSuccessCallback(session, message.data.selectedMedia);
                 }
             ];
@@ -256,6 +266,17 @@ onMessage(message => {
 
             break;
         };
+
+        /**
+         * Popup closed before session established.
+         */
+        case "shim:popupClosed": {
+            if (state.sessionRequestInProgress) {
+                state.sessionRequestInProgress = false;
+                sessionErrorCallback(new Error_(ErrorCode.CANCEL));
+            }
+            break;
+        }
     }
 });
 

ext/src/shim/state.js

@@ -1,10 +1,11 @@
-"use strict";
-
-// Global API state
-const state = {
-    apiConfig: null
-  , receiverList: []
-  , sessionList: []
-};
-
-export default state;
+"use strict";
+
+// Global API state
+const state = {
+    apiConfig: null
+  , receiverList: []
+  , sessionList: []
+  , sessionRequestInProgress: false
+};
+
+export default state;