fix(core): create root directory before extracting files

This fixes a bug where files in the root directory of an archive
would not be extracted if they are encountered before any other directory.
The reason is that QFile::open() cannot create directories.

src/libs/core/extractor.cpp

@@ -59,6 +59,9 @@ void Extractor::extract(const QString &sourceFile, const QString &destination, c
         destinationDir.setPath(destinationDir.filePath(root));
     }
 
+    // Destination directory must be created before any other files.
+    destinationDir.mkpath(QLatin1String("."));
+
     // TODO: Do not strip root directory in archive if it equals to 'root'
     archive_entry *entry;
     while (archive_read_next_header(info.archiveHandle, &entry) == ARCHIVE_OK) {