Add an abstracted interface around android-specific handling

* This makes it easier to use the same kind of interface to manage other kinds
  of devices.

qrenderdoc/Windows/MainWindow.h

@@ -256,5 +256,5 @@ private:
 
   void showLaunchError(ReplayStatus status);
 
-  bool isCapturableAppRunningOnAndroid();
+  bool isUnshareableDeviceInUse();
 };