Implement tracing interface for v8

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 7b4d2746d7de9a27b9e961ac71d1a57b8282f1e7..00a59e413e66eb533df3fe8860ce7619f29d722c 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -135,6 +135,28 @@ class PredictablePlatform : public Platform {
     return synthetic_time_in_sec_ += 0.00001;
   }
 
+  uint64_t AddTraceEvent(char phase, const uint8_t* categoryEnabledFlag,
+                         const char* name, uint64_t 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:
   double synthetic_time_in_sec_ = 0.0;