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

Review URL: https://codereview.chromium.org/1316233002
diff --git a/samplecode/SampleFuzz.cpp b/samplecode/SampleFuzz.cpp
index e690df1..d1a696f 100644
--- a/samplecode/SampleFuzz.cpp
+++ b/samplecode/SampleFuzz.cpp
@@ -383,7 +383,7 @@
 
     virtual void onDrawContent(SkCanvas* canvas) {
         do_fuzz(canvas);
-        this->inval(NULL);
+        this->inval(nullptr);
     }
 
 private: