[CMFileManager] Always display searching progress after back to the search result view

1.Go into the root directory, click the search icon and input the directory name(Such as: dlt).
2.In Search results view, you can see the dlt directory, then click the directory.
3.press back key, back to the Search results view, the lower right corner's searching progress has always show.

After Seaching, the searching progress shouldn't show.

Change-Id: Id1a3291effcebcd7c9536dec74175d6d019e83f1