WindowServer: Clear wallpaper if the requested path is empty

235f39e449 secretly added an if check that ignores all the files that
couldn't be loaded into bitmaps.  Unfortunately, we send an empty path
as a way to unset the wallpaper, which meant that we couldn't go back
to the default background color anymore.

1 files changed, 5 insertions, 2 deletions

diff --git a/Userland/Services/WindowServer/Compositor.cpp b/Userland/Services/WindowServer/Compositor.cpp
index f1b65b4a80..68cff53096 100644
--- a/Userland/Services/WindowServer/Compositor.cpp
+++ b/Userland/Services/WindowServer/Compositor.cpp
@@ -813,12 +813,15 @@ bool Compositor::set_wallpaper(const String& path, Function<void(bool)>&& callba
         },
 
         [this, path, callback = move(callback)](ErrorOr<NonnullRefPtr<Gfx::Bitmap>> bitmap) {
-            if (bitmap.is_error()) {
+            if (bitmap.is_error() && !path.is_empty()) {
                 callback(false);
                 return;
             }
             m_wallpaper_path = path;
-            m_wallpaper = bitmap.release_value();
+            if (bitmap.is_error())
+                m_wallpaper = nullptr;
+            else
+                m_wallpaper = bitmap.release_value();
             invalidate_screen();
             callback(true);
         });