Run clang-tidy with modernize nullptr

Also add two enum values in the qt5 frontend to representate no flags
Also mark glib/gtk/cairo system includes so that gcc doesn't report the issues in those headers

1 files changed, 3 insertions, 3 deletions

diff --git a/poppler/CurlCachedFile.cc b/poppler/CurlCachedFile.cc
index af4c2b60..907baafe 100644
--- a/poppler/CurlCachedFile.cc
+++ b/poppler/CurlCachedFile.cc
@@ -20,9 +20,9 @@
 
 CurlCachedFileLoader::CurlCachedFileLoader()
 {
-  url = NULL;
-  cachedFile = NULL;
-  curl = NULL;
+  url = nullptr;
+  cachedFile = nullptr;
+  curl = nullptr;
 }
 
 CurlCachedFileLoader::~CurlCachedFileLoader() {