IPC: Delete thread-safe send support

content/renderer/gpu/queue_message_swap_promise_unittest.cc

Index: content/renderer/gpu/queue_message_swap_promise_unittest.cc
diff --git a/content/renderer/gpu/queue_message_swap_promise_unittest.cc b/content/renderer/gpu/queue_message_swap_promise_unittest.cc
index ffcfb94bd40d70f13aae560e74e09700ac9798d4..cc8777b6adbc3427f11989a43ae2a4701182f07b 100644
--- a/content/renderer/gpu/queue_message_swap_promise_unittest.cc
+++ b/content/renderer/gpu/queue_message_swap_promise_unittest.cc
@@ -35,7 +35,7 @@ class TestRenderWidget : public RenderWidget {
 
 class TestSyncMessageFilter : public IPC::SyncMessageFilter {
  public:
-  TestSyncMessageFilter() : IPC::SyncMessageFilter(NULL, false) {}
+  TestSyncMessageFilter() : IPC::SyncMessageFilter(nullptr) {}
 
   bool Send(IPC::Message* message) override {
     messages_.push_back(base::WrapUnique(message));