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

Review URL: https://codereview.chromium.org/1316233002
diff --git a/tests/ReadWriteAlphaTest.cpp b/tests/ReadWriteAlphaTest.cpp
index a767068..301bf6b 100644
--- a/tests/ReadWriteAlphaTest.cpp
+++ b/tests/ReadWriteAlphaTest.cpp
@@ -23,7 +23,7 @@
             continue;
         }
         GrContext* context = factory->get(glType);
-        if (NULL == context) {
+        if (nullptr == context) {
             continue;
         }