Implement tracing interface for v8

test/cctest/test-incremental-marking.cc

 // Copyright 2015 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.
 
 #include <stdlib.h>
 
 #ifdef __linux__
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
@@ skipping 62 matching lines @@
 
   bool PendingDelayedTask() { return delayed_task_ != nullptr; }
 
   void PerformDelayedTask() {
     Task* task = delayed_task_;
     delayed_task_ = nullptr;
     task->Run();
     delete task;
   }
 
+  uint64_t AddTraceEvent(char phase, const uint8_t* categoryEnabledFlag,
+                         const char* name, uint64_t id, uint64_t context_id,
+                         uint64_t bind_id, int numArgs, const char** argNames,
+                         const uint8_t* argTypes, const uint64_t* argValues,
+                         unsigned int flags) override {
+    return 0;
+  }
+
+  void UpdateTraceEventDuration(const uint8_t* categoryEnabledFlag,
+                                const char* name, uint64_t handle) override {}
+
+  const uint8_t* GetCategoryGroupEnabled(const char* name) override {
+    static uint8_t no = 0;
+    return &no;
+  }
+
+  const char* GetCategoryGroupName(
+      const uint8_t* categoryEnabledFlag) override {
+    static const char* dummy = "dummy";
+    return dummy;
+  }
+
  private:
   v8::Platform* platform_;
   IdleTask* idle_task_;
   Task* delayed_task_;
 };
 
 
 TEST(IncrementalMarkingUsingIdleTasks) {
   if (!i::FLAG_incremental_marking) return;
   CcTest::InitializeVM();
@@ skipping 66 matching lines @@
   }
   // Once we stop notifying idle task progress, the delayed tasks
   // should finish marking.
   while (!marking->IsStopped() && platform.PendingDelayedTask()) {
     platform.PerformDelayedTask();
   }
   // There could be pending delayed task from memory reducer after GC finishes.
   CHECK(marking->IsStopped());
   i::V8::SetPlatformForTesting(old_platform);
 }