shim for singleSimulator (#6009)

* shim

* update

* get shim fixed up

* plumbing hooked up...

* revert change

* rvert deletion

* swap

libs/core/_locales/core-jsdoc-strings.json

@@ -329,6 +329,7 @@
   "control.runtimeWarning": "Display warning in the simulator.",
   "control.setDebugFlags": "Set flags used when connecting an external debugger.",
   "control.simmessages.onReceived": "Registers the handler for a message on a given channel",
+  "control.singleSimulator": "Allow only one simulator",
   "control.waitForEvent": "Blocks the calling thread until the specified event is raised.",
   "control.waitMicros": "Blocks the current fiber for the given microseconds",
   "control.waitMicros|param|micros": "number of micro-seconds to wait. eg: 4",

libs/core/control.cpp

@@ -271,6 +271,12 @@ namespace control {
       microbit_reset();
     }
 
+
+    
+
+    //%
+    void singleSimulator() { }
+
     /**
     * Blocks the current fiber for the given microseconds
     * @param micros number of micro-seconds to wait. eg: 4

libs/core/control.ts

@@ -16,6 +16,14 @@ namespace control {
     export function runInBackground(a: () => void) {
         control.inBackground(a);
     }
+    
+    /**
+     * Allow only one simulator
+     */
+    //% shim=control::singleSimulator
+    export function singleSimulator() { 
+
+    }
 
     /**
      * Returns the value of a C++ runtime constant