Merge pull request #1660 from smartdevicelink/bugfix/class_cast_exp_rs

Attempt to fix unreproducible ClassCastException

Author: Robert Henigan

android/sdl_android/src/main/java/com/smartdevicelink/transport/SdlRouterService.java

@@ -3124,7 +3124,9 @@ public boolean removeSession(Long sessionId) {
             int location = sessionIds.indexOf(sessionId);
             if (location >= 0) {
                 Long removedSessionId = sessionIds.remove(location);
-                registeredTransports.remove(sessionId.intValue());
+                synchronized (TRANSPORT_LOCK) {
+                    registeredTransports.remove(sessionId.intValue());
+                }
                 return removedSessionId != null;
             } else {
                 return false;
@@ -3262,11 +3264,21 @@ protected void unregisterAllTransports(int sessionId) {
          * @return
          */
         private TransportType getCompatPrimaryTransport() {
-            if (this.registeredTransports != null && this.registeredTransports.size() > 0) {
-                List<TransportType> transportTypes = this.registeredTransports.valueAt(0);
-                if (transportTypes != null) {
-                    if (transportTypes.get(0) != null) {
-                        return transportTypes.get(0);
+            synchronized (TRANSPORT_LOCK) {
+                if (this.registeredTransports != null && this.registeredTransports.size() > 0) {
+                    Object obj = this.registeredTransports.valueAt(0);
+                    //Lint shows to ignore this call, but there are crash logs that show otherwise
+                    if (obj != null && obj instanceof List) {
+                        try {
+                            List<TransportType> transportTypes = (List<TransportType>) obj;
+                            if (transportTypes != null) {
+                                if (transportTypes.get(0) != null) {
+                                    return transportTypes.get(0);
+                                }
+                            }
+                        } catch (ClassCastException e) {
+                            DebugTool.logError(TAG, "Unable to cast transport list", e);
+                        }
                     }
                 }
             }