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

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 542143cea7af64c6cfc63ed93ba67bb66b77e5e8..e7829db683edc8a2607aecd7ee2e707e6c388011 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -141,7 +141,7 @@ class LayerTreeHostImplTimeSourceAdapter : public TimeSourceClient {
                                                time_source));
   }
   virtual ~LayerTreeHostImplTimeSourceAdapter() {
-    time_source_->SetClient(NULL);
+    time_source_->SetClient(nullptr);
     time_source_->SetActive(false);
   }
 
@@ -229,14 +229,14 @@ LayerTreeHostImpl::LayerTreeHostImpl(
       client_(client),
       proxy_(proxy),
       use_gpu_rasterization_(false),
-      input_handler_client_(NULL),
+      input_handler_client_(nullptr),
       did_lock_scrolling_layer_(false),
       should_bubble_scrolls_(false),
       wheel_scrolling_(false),
       scroll_affects_scroll_handler_(false),
       scroll_layer_id_when_mouse_over_scrollbar_(0),
       tile_priorities_dirty_(false),
-      root_layer_scroll_offset_delegate_(NULL),
+      root_layer_scroll_offset_delegate_(nullptr),
       settings_(settings),
       visible_(true),
       cached_managed_memory_policy_(
@@ -300,7 +300,7 @@ LayerTreeHostImpl::~LayerTreeHostImpl() {
 
   if (input_handler_client_) {
     input_handler_client_->WillShutdown();
-    input_handler_client_ = NULL;
+    input_handler_client_ = nullptr;
   }
 
   // The layer trees must be destroyed before the layer tree host. We've
@@ -376,7 +376,7 @@ bool LayerTreeHostImpl::CanDraw() const {
     return false;
   }
 
-  // Must have an OutputSurface if |renderer_| is not NULL.
+  // Must have an OutputSurface if |renderer_| is not nullptr.
   DCHECK(output_surface_);
 
   // TODO(boliu): Make draws without root_layer work and move this below
@@ -451,7 +451,7 @@ bool LayerTreeHostImpl::IsCurrentlyScrollingLayerAt(
 
   bool scroll_on_main_thread = false;
   LayerImpl* scrolling_layer_impl = FindScrollLayerForDeviceViewportPoint(
-      device_viewport_point, type, layer_impl, &scroll_on_main_thread, NULL);
+      device_viewport_point, type, layer_impl, &scroll_on_main_thread, nullptr);
   return CurrentlyScrollingLayer() == scrolling_layer_impl;
 }
 
@@ -465,14 +465,14 @@ bool LayerTreeHostImpl::HaveTouchEventHandlersAt(
       active_tree_->FindLayerThatIsHitByPointInTouchHandlerRegion(
           device_viewport_point);
 
-  return layer_impl != NULL;
+  return layer_impl != nullptr;
 }
 
 scoped_ptr<SwapPromiseMonitor>
 LayerTreeHostImpl::CreateLatencyInfoSwapPromiseMonitor(
     ui::LatencyInfo* latency) {
   return make_scoped_ptr(
-      new LatencyInfoSwapPromiseMonitor(latency, NULL, this));
+      new LatencyInfoSwapPromiseMonitor(latency, nullptr, this));
 }
 
 void LayerTreeHostImpl::QueueSwapPromiseForMainThreadScrollUpdate(
@@ -716,7 +716,7 @@ DrawResult LayerTreeHostImpl::CalculateRenderPasses(
     RenderSurfaceImpl* render_surface = render_surface_layer->render_surface();
 
     bool should_draw_into_render_pass =
-        render_surface_layer->parent() == NULL ||
+        render_surface_layer->parent() == nullptr ||
         render_surface->contributes_to_drawn_surface() ||
         render_surface_layer->HasCopyRequest();
     if (should_draw_into_render_pass)
@@ -964,7 +964,7 @@ static inline RenderPass* FindRenderPassById(
     const LayerTreeHostImpl::FrameData& frame) {
   RenderPassIdHashMap::const_iterator it =
       frame.render_passes_by_id.find(render_pass_id);
-  return it != frame.render_passes_by_id.end() ? it->second : NULL;
+  return it != frame.render_passes_by_id.end() ? it->second : nullptr;
 }
 
 static void RemoveRenderPassesRecursive(RenderPassId remove_render_pass_id,
@@ -1251,7 +1251,7 @@ void LayerTreeHostImpl::GetPictureLayerImplPairs(
     // Ignore the twin layer when tile priorities are invalid.
     // TODO(vmpstr): Iterators should handle this instead. crbug.com/381704
     if (twin_layer && !twin_layer->HasValidTilePriorities())
-      twin_layer = NULL;
+      twin_layer = nullptr;
 
     // If the current tree is ACTIVE_TREE, then always generate a layer_pair.
     // If current tree is PENDING_TREE, then only generate a layer_pair if
@@ -1260,7 +1260,7 @@ void LayerTreeHostImpl::GetPictureLayerImplPairs(
       DCHECK(!twin_layer || twin_layer->GetTree() == PENDING_TREE);
       layer_pairs->push_back(PictureLayerImpl::Pair(layer, twin_layer));
     } else if (!twin_layer) {
-      layer_pairs->push_back(PictureLayerImpl::Pair(NULL, layer));
+      layer_pairs->push_back(PictureLayerImpl::Pair(nullptr, layer));
     }
   }
 }
@@ -1547,7 +1547,8 @@ void LayerTreeHostImpl::DrawLayers(FrameData* frame,
         IsCurrentlyScrolling() || needs_animate_layers();
 
     scoped_ptr<SoftwareRenderer> temp_software_renderer =
-        SoftwareRenderer::Create(this, &settings_, output_surface_.get(), NULL);
+        SoftwareRenderer::Create(
+            this, &settings_, output_surface_.get(), nullptr);
     temp_software_renderer->DrawFrame(&frame->render_passes,
                                       device_scale_factor_,
                                       DeviceViewport(),
@@ -1714,7 +1715,7 @@ bool LayerTreeHostImpl::IsCurrentlyScrolling() const {
 // this function returns the associated scroll layer if any.
 static LayerImpl* FindScrollLayerForContentLayer(LayerImpl* layer_impl) {
   if (!layer_impl)
-    return NULL;
+    return nullptr;
 
   if (layer_impl->scrollable())
     return layer_impl;
@@ -1724,7 +1725,7 @@ static LayerImpl* FindScrollLayerForContentLayer(LayerImpl* layer_impl) {
       layer_impl->parent()->scrollable())
     return layer_impl->parent();
 
-  return NULL;
+  return nullptr;
 }
 
 void LayerTreeHostImpl::CreatePendingTree() {
@@ -1760,7 +1761,7 @@ void LayerTreeHostImpl::ActivateSyncTree() {
   if (pending_tree_) {
     TRACE_EVENT_ASYNC_END0("cc", "PendingTree:waiting", pending_tree_.get());
 
-    active_tree_->SetRootLayerScrollOffsetDelegate(NULL);
+    active_tree_->SetRootLayerScrollOffsetDelegate(nullptr);
     active_tree_->PushPersistedState(pending_tree_.get());
     // Process any requests in the UI resource queue.  The request queue is
     // given in LayerTreeHost::FinishCommitOnImplThread.  This must take place
@@ -2225,7 +2226,7 @@ float LayerTreeHostImpl::ControlsTopOffset() const {
 }
 
 void LayerTreeHostImpl::BindToClient(InputHandlerClient* client) {
-  DCHECK(input_handler_client_ == NULL);
+  DCHECK(input_handler_client_ == nullptr);
   input_handler_client_ = client;
 }
 
@@ -2244,14 +2245,14 @@ LayerImpl* LayerTreeHostImpl::FindScrollLayerForDeviceViewportPoint(
   DCHECK(scroll_on_main_thread);
 
   // Walk up the hierarchy and look for a scrollable layer.
-  LayerImpl* potentially_scrolling_layer_impl = NULL;
+  LayerImpl* potentially_scrolling_layer_impl = nullptr;
   for (; layer_impl; layer_impl = NextScrollLayer(layer_impl)) {
     // The content layer can also block attempts to scroll outside the main
     // thread.
     ScrollStatus status = layer_impl->TryScroll(device_viewport_point, type);
     if (status == ScrollOnMainThread) {
       *scroll_on_main_thread = true;
-      return NULL;
+      return nullptr;
     }
 
     LayerImpl* scroll_layer_impl = FindScrollLayerForContentLayer(layer_impl);
@@ -2262,7 +2263,7 @@ LayerImpl* LayerTreeHostImpl::FindScrollLayerForDeviceViewportPoint(
     // If any layer wants to divert the scroll event to the main thread, abort.
     if (status == ScrollOnMainThread) {
       *scroll_on_main_thread = true;
-      return NULL;
+      return nullptr;
     }
 
     if (optional_has_ancestor_scroll_handler &&
@@ -2694,7 +2695,7 @@ void LayerTreeHostImpl::SetRootLayerScrollOffsetDelegate(
 }
 
 void LayerTreeHostImpl::OnRootLayerDelegatedScrollOffsetChanged() {
-  DCHECK(root_layer_scroll_offset_delegate_ != NULL);
+  DCHECK(root_layer_scroll_offset_delegate_ != nullptr);
   client_->SetNeedsCommitOnImplThread();
   active_tree_->set_needs_update_draw_properties();
 }
@@ -2767,7 +2768,7 @@ void LayerTreeHostImpl::MouseMoveAt(const gfx::Point& viewport_point) {
     // TODO(wjmaclean) Add a unit test if this fixes the crashes.
     ScrollbarAnimationController* animation_controller =
         scroll_layer_impl ? scroll_layer_impl->scrollbar_animation_controller()
-                          : NULL;
+                          : nullptr;
     if (animation_controller)
       animation_controller->DidMouseMoveOffScrollbar();
     scroll_layer_id_when_mouse_over_scrollbar_ = 0;
@@ -2779,7 +2780,7 @@ void LayerTreeHostImpl::MouseMoveAt(const gfx::Point& viewport_point) {
                                             InputHandler::Gesture,
                                             layer_impl,
                                             &scroll_on_main_thread,
-                                            NULL);
+                                            nullptr);
   if (scroll_on_main_thread || !scroll_layer_impl)
     return;
 
@@ -2846,7 +2847,7 @@ void LayerTreeHostImpl::PinchGestureUpdate(float magnify_delta,
   // For a moment the scroll offset ends up being outside of the max range. This
   // confuses the delegate so we switch it off till after we're done processing
   // the pinch update.
-  active_tree_->SetRootLayerScrollOffsetDelegate(NULL);
+  active_tree_->SetRootLayerScrollOffsetDelegate(nullptr);
 
   // Keep the center-of-pinch anchor specified by (x, y) in a stable
   // position over the course of the magnify.
@@ -3149,12 +3150,12 @@ BeginFrameArgs LayerTreeHostImpl::CurrentBeginFrameArgs() const {
 }
 
 void LayerTreeHostImpl::AsValueInto(base::debug::TracedValue* value) const {
-  return AsValueWithFrameInto(NULL, value);
+  return AsValueWithFrameInto(nullptr, value);
 }
 
 scoped_refptr<base::debug::ConvertableToTraceFormat>
 LayerTreeHostImpl::AsValue() const {
-  return AsValueWithFrame(NULL);
+  return AsValueWithFrame(nullptr);
 }
 
 scoped_refptr<base::debug::ConvertableToTraceFormat>