When saving covers in the conver dialog, if dest folder does not exist then save in the cache folder.

ChangeLog

@@ -78,6 +78,8 @@
 56. Fix context widget backdrop retrieval from fan-art
 57. Fix/work-around Qt 5.5 issues with QMenu being used in 2 actions.
 58. When looking for covers, also check sub-folders and return first image.
+59. When saving covers in the conver dialog, if dest folder does not exisy then
+    save in the cache folder.
 
 1.5.2
 -----

gui/coverdialog.cpp

@@ -1287,6 +1287,7 @@ bool CoverDialog::saveCover(const QString &src, const QImage &img)
             dirName=filePath.endsWith('/') ? (haveAbsPath ? QString() : mpdDir)+filePath
                                             : Utils::getDir((haveAbsPath ? QString() : mpdDir)+filePath);
         }
+        saveInMpd=QDir(dirName).exists();
     }
 
     if (isArtist) {