"NULL !=" = NULL

R=reed@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/544233002
diff --git a/samplecode/SampleChart.cpp b/samplecode/SampleChart.cpp
index 630ff6e..12a6afe 100644
--- a/samplecode/SampleChart.cpp
+++ b/samplecode/SampleChart.cpp
@@ -60,7 +60,7 @@
         x += xDelta;
     }
 
-    if (NULL != bottomData) {
+    if (bottomData) {
         SkASSERT(bottomData->count() == topData.count());
         // iterate backwards over the previous graph's data to generate the bottom of the filled
         // area (and account for leftShift).