[C++11 Allowed Features] Declares a type-safe null pointer converting from NULL to nullptr in src/…

cc/resources/pixel_buffer_raster_worker_pool.cc

Index: cc/resources/pixel_buffer_raster_worker_pool.cc
diff --git a/cc/resources/pixel_buffer_raster_worker_pool.cc b/cc/resources/pixel_buffer_raster_worker_pool.cc
index 693f643a8015df693a6d95a97d137a8e8695469e..895ff04a6aca7fc0984abe7852d1f706f539571d 100644
--- a/cc/resources/pixel_buffer_raster_worker_pool.cc
+++ b/cc/resources/pixel_buffer_raster_worker_pool.cc
@@ -25,7 +25,7 @@ class RasterBufferImpl : public RasterBuffer {
                    const Resource* resource)
       : resource_provider_(resource_provider),
         resource_(resource),
-        buffer_(NULL),
+        buffer_(nullptr),
         stride_(0) {
     resource_provider_->AcquirePixelBuffer(resource_->id());
     buffer_ = resource_provider_->MapPixelBuffer(resource_->id(), &stride_);