Fix destruction order between SurfaceManger and OffscreenCanvasSurfaceImpl

cc/surfaces/surface_factory.cc

Index: cc/surfaces/surface_factory.cc
diff --git a/cc/surfaces/surface_factory.cc b/cc/surfaces/surface_factory.cc
index d56b3174a8cc41d399468e8def7dc3991b3cdd17..f34fafc40fd0b39f2923fb6340119bf1aedee1ea 100644
--- a/cc/surfaces/surface_factory.cc
+++ b/cc/surfaces/surface_factory.cc
@@ -32,14 +32,18 @@ SurfaceFactory::~SurfaceFactory() {
 }
 
 void SurfaceFactory::DestroyAll() {
+  if (manager_) {
   for (auto& pair : surface_map_)
     manager_->Destroy(std::move(pair.second));
+
   surface_map_.clear();
+  }
 }
 
 void SurfaceFactory::Create(SurfaceId surface_id) {
   std::unique_ptr<Surface> surface(new Surface(surface_id, this));
-  manager_->RegisterSurface(surface.get());
+  if (manager_)
+    manager_->RegisterSurface(surface.get());
   DCHECK(!surface_map_.count(surface_id));
   surface_map_[surface_id] = std::move(surface);
 }
@@ -50,7 +54,8 @@ void SurfaceFactory::Destroy(SurfaceId surface_id) {
   DCHECK(it->second->factory().get() == this);
   std::unique_ptr<Surface> surface(std::move(it->second));
   surface_map_.erase(it);
-  manager_->Destroy(std::move(surface));
+  if (manager_)
+    manager_->Destroy(std::move(surface));
 }
 
 void SurfaceFactory::SetPreviousFrameSurface(SurfaceId new_id,