Style Change: NULL->nullptr
DOCS_PREVIEW= https://skia.org/?cl=1316233002

Review URL: https://codereview.chromium.org/1316233002
diff --git a/tests/PDFDocumentTest.cpp b/tests/PDFDocumentTest.cpp
index f9fcdff..04c3ede 100644
--- a/tests/PDFDocumentTest.cpp
+++ b/tests/PDFDocumentTest.cpp
@@ -82,7 +82,7 @@
     doc->close();
 
     FILE* file = fopen(path.c_str(), "r");
-    REPORTER_ASSERT(reporter, file != NULL);
+    REPORTER_ASSERT(reporter, file != nullptr);
     char header[100];
     REPORTER_ASSERT(reporter, fread(header, 4, 1, file) != 0);
     REPORTER_ASSERT(reporter, strncmp(header, "%PDF", 4) == 0);