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

Review URL: https://codereview.chromium.org/1316233002
diff --git a/src/effects/gradients/SkGradientBitmapCache.cpp b/src/effects/gradients/SkGradientBitmapCache.cpp
index 90fa3d5..24e7f58 100644
--- a/src/effects/gradients/SkGradientBitmapCache.cpp
+++ b/src/effects/gradients/SkGradientBitmapCache.cpp
@@ -18,8 +18,8 @@
     SkBitmap    fBitmap;
 
     Entry(const void* buffer, size_t size, const SkBitmap& bm)
-            : fPrev(NULL),
-              fNext(NULL),
+            : fPrev(nullptr),
+              fNext(nullptr),
               fBitmap(bm) {
         fBuffer = sk_malloc_throw(size);
         fSize = size;
@@ -35,7 +35,7 @@
 
 SkGradientBitmapCache::SkGradientBitmapCache(int max) : fMaxEntries(max) {
     fEntryCount = 0;
-    fHead = fTail = NULL;
+    fHead = fTail = nullptr;
 
     this->validate();
 }
@@ -70,7 +70,7 @@
 }
 
 void SkGradientBitmapCache::attachToHead(Entry* entry) const {
-    entry->fPrev = NULL;
+    entry->fPrev = nullptr;
     entry->fNext = fHead;
     if (fHead) {
         fHead->fPrev = entry;
@@ -121,8 +121,8 @@
     SkASSERT(fEntryCount >= 0 && fEntryCount <= fMaxEntries);
 
     if (fEntryCount > 0) {
-        SkASSERT(NULL == fHead->fPrev);
-        SkASSERT(NULL == fTail->fNext);
+        SkASSERT(nullptr == fHead->fPrev);
+        SkASSERT(nullptr == fTail->fNext);
 
         if (fEntryCount == 1) {
             SkASSERT(fHead == fTail);
@@ -145,8 +145,8 @@
         }
         SkASSERT(0 == count);
     } else {
-        SkASSERT(NULL == fHead);
-        SkASSERT(NULL == fTail);
+        SkASSERT(nullptr == fHead);
+        SkASSERT(nullptr == fTail);
     }
 }