[android] clear camera callbacks' message queue when the map is destroyed

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/CameraChangeDispatcher.java

@@ -142,6 +142,14 @@ class CameraChangeDispatcher implements MapboxMap.OnCameraMoveStartedListener, M
     }
   }
 
+  void onDestroy() {
+    handler.removeCallbacksAndMessages(null);
+    onCameraMoveStarted.clear();
+    onCameraMoveCanceled.clear();
+    onCameraMove.clear();
+    onCameraIdle.clear();
+  }
+
   private static class CameraChangeHandler extends Handler {
 
     private WeakReference<CameraChangeDispatcher> dispatcherWeakReference;

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapboxMap.java

@@ -176,6 +176,7 @@ public final class MapboxMap {
     if (style != null) {
       style.clear();
     }
+    cameraChangeDispatcher.onDestroy();
   }
 
   /**