[corelib] dart:developer timeline flow events

runtime/vm/timeline_fuchsia.cc

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(HOST_OS_FUCHSIA) && !defined(PRODUCT)
 
 #include "apps/tracing/lib/trace/cwriter.h"
 #include "apps/tracing/lib/trace/event.h"
 #include "vm/object.h"
@@ skipping 170 matching lines @@
                                                    const char* args) {
   const int64_t end = OS::GetCurrentMonotonicMicros();
   const int64_t end_cpu = OS::GetCurrentThreadCPUMicros();
   event->Duration(strdup(name), start, end, start_cpu, end_cpu);
   event->set_owns_label(true);
   event->SetNumArguments(1);
   event->CopyArgument(0, "args", args);
   event->Complete();
 }
 
+void DartTimelineEventHelpers::ReportFlowEvent(Thread* thread,
+                                               Zone* zone,
+                                               TimelineEvent* event,
+                                               int64_t start,
+                                               int64_t start_cpu,
+                                               const char* category,
+                                               const char* name,
+                                               int64_t type,
+                                               int64_t flow_id,
+                                               const char* args) {
+  char* name_string = strdup(name);
+  ASSERT((type >= 0) && (type <= 2));
+  switch (type) {
+    case 0:
+      event->FlowBegin(name_string, flow_id, start);
+      break;
+    case 1:
+      event->FlowStep(name_string, flow_id, start);
+      break;
+    case 2:
+      event->FlowEnd(name_string, flow_id, start);
+      break;
+    default:
+      UNREACHABLE();
+      break;
+  }
+  event->set_owns_label(true);
+  event->SetNumArguments(1);
+  event->CopyArgument(0, "args", args);
+  event->Complete();
+}
+
 void DartTimelineEventHelpers::ReportInstantEvent(Thread* thread,
                                                   Zone* zone,
                                                   TimelineEvent* event,
                                                   int64_t start,
                                                   const char* category,
                                                   const char* name,
                                                   const char* args) {
   event->Instant(strdup(name), start);
   event->set_owns_label(true);
   event->SetNumArguments(1);
   event->CopyArgument(0, "args", args);
   event->Complete();
 }
 
 }  // namespace dart
 
 #endif  // defined(HOST_OS_FUCHSIA) && !defined(PRODUCT)