Move microtask queueing logic from JavaScript to C++

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include "../include/v8-debug.h"
 #include "allocation.h"
 #include "assert-scope.h"
@@ skipping 331 matching lines @@
   V(FunctionInfoListener*, active_function_info_listener, NULL)                \
   /* State for Relocatable. */                                                 \
   V(Relocatable*, relocatable_top, NULL)                                       \
   V(DebugObjectCache*, string_stream_debug_object_cache, NULL)                 \
   V(Object*, string_stream_current_security_token, NULL)                       \
   /* Serializer state. */                                                      \
   V(ExternalReferenceTable*, external_reference_table, NULL)                   \
   /* AstNode state. */                                                         \
   V(int, ast_node_id, 0)                                                       \
   V(unsigned, ast_node_count, 0)                                               \
-  V(bool, microtask_pending, false)                                            \
+  V(int, pending_microtask_count, 0)                                           \
   V(bool, autorun_microtasks, true)                                            \
   V(HStatistics*, hstatistics, NULL)                                           \
   V(HTracer*, htracer, NULL)                                                   \
   V(CodeTracer*, code_tracer, NULL)                                            \
   V(bool, fp_stubs_generated, false)                                           \
   V(int, max_available_threads, 0)                                             \
   V(uint32_t, per_isolate_assert_data, 0xFFFFFFFFu)                            \
   V(InterruptCallback, api_interrupt_callback, NULL)                           \
   V(void*, api_interrupt_callback_data, NULL)                                  \
   ISOLATE_INIT_SIMULATOR_LIST(V)
@@ skipping 697 matching lines @@
     return id;
   }
 
   // Get (and lazily initialize) the registry for per-isolate symbols.
   Handle<JSObject> GetSymbolRegistry();
 
   void AddCallCompletedCallback(CallCompletedCallback callback);
   void RemoveCallCompletedCallback(CallCompletedCallback callback);
   void FireCallCompletedCallback();
 
+  void EnqueueMicrotask(Handle<JSFunction> microtask);
   void RunMicrotasks();
 
  private:
   Isolate();
 
   friend struct GlobalState;
   friend struct InitializeGlobalState;
 
   enum State {
     UNINITIALIZED,    // Some components may not have been allocated.
@@ skipping 399 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_