KDirectoryContentsCounter: show intermediate dir size counting results, improve stopping, improve data caching

Two user visible changes:
 * we can see the dir size changing as it is updated.
 * This makes the file counting a lot more reactive, when changing directories for instance.

`KDirectoryContentsCounterWorker::walkDir` is not recursive anymore.

The cache is now shared and only a single thread is used to count size recursively.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/kitemviews/kfileitemmodel.h b/src/kitemviews/kfileitemmodel.h
index afcd633b0..721569a0c 100644
--- a/src/kitemviews/kfileitemmodel.h
+++ b/src/kitemviews/kfileitemmodel.h
@@ -218,6 +218,11 @@ Q_SIGNALS:
     void directoryLoadingCompleted();
 
     /**
+     * Is emitted when the model is being refreshed (F5 key press)
+     */
+    void directoryRefreshing();
+
+    /**
      * Is emitted after the loading of a directory has been canceled.
      */
     void directoryLoadingCanceled();