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

Review URL: https://codereview.chromium.org/1316233002
diff --git a/src/gpu/GrResourceProvider.h b/src/gpu/GrResourceProvider.h
index f0f28ff..72efab1 100644
--- a/src/gpu/GrResourceProvider.h
+++ b/src/gpu/GrResourceProvider.h
@@ -50,7 +50,7 @@
      * @param vertCount   number of vertices the pattern references
      * @param key         Key to be assigned to the index buffer.
      *
-     * @return The index buffer if successful, otherwise NULL.
+     * @return The index buffer if successful, otherwise nullptr.
      */
     const GrIndexBuffer* findOrCreateInstancedIndexBuffer(const uint16_t* pattern,
                                                           int patternSize,
@@ -129,7 +129,7 @@
      *   @param data             User supplied data which will be passed into func whenver an
      *                           eviction occurs
      *
-     *   @return                 An initialized GrBatchAtlas, or NULL if creation fails
+     *   @return                 An initialized GrBatchAtlas, or nullptr if creation fails
      */
     GrBatchAtlas* createAtlas(GrPixelConfig, int width, int height, int numPlotsX, int numPlotsY,
                               GrBatchAtlas::EvictionFunc func, void* data);