Style Change: NULL->nullptr

src/effects/SkDisplacementMapEffect.cpp

Index: src/effects/SkDisplacementMapEffect.cpp
diff --git a/src/effects/SkDisplacementMapEffect.cpp b/src/effects/SkDisplacementMapEffect.cpp
index 62fca7b14d8ad6244d51855bb9099a2288525e83..90442843005eabb07a490b194edb651e27f766ab 100644
--- a/src/effects/SkDisplacementMapEffect.cpp
+++ b/src/effects/SkDisplacementMapEffect.cpp
@@ -169,7 +169,7 @@ SkDisplacementMapEffect* SkDisplacementMapEffect::Create(ChannelSelectorType xCh
                                                          const CropRect* cropRect) {
     if (!channel_selector_type_is_valid(xChannelSelector) ||
         !channel_selector_type_is_valid(yChannelSelector)) {
-        return NULL;
+        return nullptr;
     }
 
     SkImageFilter* inputs[2] = { displacement, color };