[v8] Drop support for non-CppGC v8::MicrotaskQueue (#261)

... as this support is already removed from V8.

Author: isheludko

common.gypi

@@ -547,9 +547,6 @@
       ['tsan == 1', {
         'defines': ['V8_IS_TSAN',],
       }],
-      ['v8_cppgc_microtask_queue == 1', {
-        'defines': ['V8_CPPGC_MICROTASK_QUEUE',],
-      }],
       ['OS == "win"', {
         'defines': [
           'WIN32',

src/node_contextify.cc

@@ -155,11 +155,7 @@ ContextifyContext* ContextifyContext::New(Environment* env,
 
   MicrotaskQueue* queue =
       options->own_microtask_queue
-#ifdef V8_CPPGC_MICROTASK_QUEUE
           ? options->own_microtask_queue
-#else
-          ? options->own_microtask_queue.get()
-#endif
           : env->isolate()->GetCurrentContext()->GetMicrotaskQueue();
 
   Local<Context> v8_context;
@@ -180,13 +176,7 @@ ContextifyContext::ContextifyContext(Environment* env,
                                      Local<Object> wrapper,
                                      Local<Context> v8_context,
                                      ContextOptions* options)
-#ifdef V8_CPPGC_MICROTASK_QUEUE
     : microtask_queue_(options->own_microtask_queue)
-#else
-    : microtask_queue_(options->own_microtask_queue
-                           ? options->own_microtask_queue.release()
-                           : nullptr)
-#endif
 {
   CppgcMixin::Wrap(this, env, wrapper);
 

test/cctest/test_environment.cc

@@ -750,11 +750,7 @@ TEST_F(EnvironmentTest, NestedMicrotaskQueue) {
   const v8::HandleScope handle_scope(isolate_);
   const Argv argv;
 
-#ifdef V8_CPPGC_MICROTASK_QUEUE
   v8::MicrotaskQueue*
-#else
-  std::unique_ptr<v8::MicrotaskQueue>
-#endif
       queue =
           v8::MicrotaskQueue::New(isolate_, v8::MicrotasksPolicy::kExplicit);
 
@@ -764,11 +760,7 @@ TEST_F(EnvironmentTest, NestedMicrotaskQueue) {
                        {},
                        {},
                        v8::DeserializeInternalFieldsCallback(),
-#ifdef V8_CPPGC_MICROTASK_QUEUE
                        queue
-#else
-                       queue.get()
-#endif
       );
   node::InitializeContext(context);
   v8::Context::Scope context_scope(context);