v8_platform.cc: Added AddTraceEventWithTimestamp

This commit adds AddTraceEventWithTimestamp to the implementation
gin::V8Platform::TracingControllerImpl.

Bug: 953949
Change-Id: I73aa361feeaf74bcaaf2e6cfd00dce761227f5a5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1572583
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653766}

AUTHORS

@@ -770,6 +770,7 @@ Ryan Sleevi <ryan-chromium-dev@sleevi.com>
 Ryan Yoakum <ryoakum@skobalt.com>
 Ryuan Choi <ryuan.choi@samsung.com>
 Saikrishna Arcot <saiarcot895@gmail.com>
+Sajal Khandelwal <skhandelwa22@bloomberg.net>
 Salvatore Iovene <salvatore.iovene@intel.com>
 Sam Larison <qufighter@gmail.com>
 Sam McDonald <sam@sammcd.com>

gin/v8_platform.cc

@@ -321,6 +321,36 @@ class V8Platform::TracingControllerImpl : public v8::TracingController {
     memcpy(&result, &handle, sizeof(result));
     return result;
   }
+  uint64_t AddTraceEventWithTimestamp(
+      char phase,
+      const uint8_t* category_enabled_flag,
+      const char* name,
+      const char* scope,
+      uint64_t id,
+      uint64_t bind_id,
+      int32_t num_args,
+      const char** arg_names,
+      const uint8_t* arg_types,
+      const uint64_t* arg_values,
+      std::unique_ptr<v8::ConvertableToTraceFormat>* arg_convertables,
+      unsigned int flags,
+      int64_t timestampMicroseconds) override {
+    base::trace_event::TraceArguments args(
+        num_args, arg_names, arg_types,
+        reinterpret_cast<const unsigned long long*>(arg_values),
+        arg_convertables);
+    DCHECK_LE(num_args, 2);
+    base::TimeTicks timestamp =
+        base::TimeTicks() +
+        base::TimeDelta::FromMicroseconds(timestampMicroseconds);
+    base::trace_event::TraceEventHandle handle =
+        TRACE_EVENT_API_ADD_TRACE_EVENT_WITH_THREAD_ID_AND_TIMESTAMP(
+            phase, category_enabled_flag, name, scope, id, bind_id,
+            TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, &args, flags);
+    uint64_t result;
+    memcpy(&result, &handle, sizeof(result));
+    return result;
+  }
   void UpdateTraceEventDuration(const uint8_t* category_enabled_flag,
                                 const char* name,
                                 uint64_t handle) override {