Code cleanup.

src/main/java/de/dennisguse/opentracks/adapters/ExecutorListViewService.java

@@ -38,7 +38,7 @@ class ExecutorListViewService<T> {
         }
 
         new Thread(() -> {
-            Future future = executorService.submit(runnable);
+            Future<?> future = executorService.submit(runnable);
             try {
                 future.get();
             } catch (ExecutionException | InterruptedException e) {

src/main/java/de/dennisguse/opentracks/adapters/MarkerResourceCursorAdapter.java

@@ -34,7 +34,7 @@ public class MarkerResourceCursorAdapter extends ResourceCursorAdapter implement
     private final Activity activity;
 
     //TODO Should be Marker.Id
-    private final ExecutorListViewService<Long> executorService = new ExecutorListViewService<Long>(LIST_PREFERRED_ITEM_HEIGHT_DEFAULT);
+    private final ExecutorListViewService<Long> executorService = new ExecutorListViewService<>(LIST_PREFERRED_ITEM_HEIGHT_DEFAULT);
 
     private boolean scroll = false;