Add top-level async trace events for the main startup timings.

base/trace_event/trace_event_common.h

Index: base/trace_event/trace_event_common.h
diff --git a/base/trace_event/trace_event_common.h b/base/trace_event/trace_event_common.h
index aa5a4935362686ede2f1c1935fb9448fbb7663a9..3c760ebcfa14a108a3306be0b8bdbd19337380e9 100644
--- a/base/trace_event/trace_event_common.h
+++ b/base/trace_event/trace_event_common.h
@@ -603,6 +603,12 @@
   INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
       TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,            \
       TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP1(                           \
+    category_group, name, id, timestamp, arg1_name, arg1_val)              \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                      \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,             \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE, \
+      arg1_name, arg1_val)
 #define TRACE_EVENT_COPY_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, id, \
                                                      timestamp)                \
   INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
@@ -686,6 +692,12 @@
   INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
       TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,            \
       TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP1(category_group, name, id,       \
+                                              timestamp, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
+      arg1_name, arg1_val)
 
 // NESTABLE_ASYNC_* APIs are used to describe an async operation, which can
 // be nested within a NESTABLE_ASYNC event and/or have inner NESTABLE_ASYNC