[vm] Reduce duplication when writing Perfetto packets

Consolidate code populating TracePacket in a single
function instead of multiple helpers. Most of the
duplication in the previous code was caused by
how Duration events were handled - this CL
avoids this duplication by making the core helper
takes event_type, timestamp and timeline event.

This allows to perform Duration split simply by
doing:

  PopulateAndWritePacket(TimelineEvent::kBegin, event.TimeOrigin(), event);
  PopulateAndWritePacket(TimelineEvent::kEnd, event.TimeEnd(), event);

Instead of duplicating large chunks of code.

TEST=ci

Change-Id: Ica5d00264f3e872b939059ea90fcbfbf6c8768e4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/417201
Reviewed-by: Derek Xu <[email protected]>

Author: mraleph

pkg/vm_service_protos/lib/src/protos/perfetto/trace/track_event/track_event.pb.dart

@@ -151,7 +151,7 @@ class TrackEvent extends $pb.GeneratedMessage {
         4, _omitFieldNames ? '' : 'debugAnnotations', $pb.PbFieldType.PM,
         subBuilder: $1.DebugAnnotation.create)
     ..e<TrackEvent_Type>(9, _omitFieldNames ? '' : 'type', $pb.PbFieldType.OE,
-        defaultOrMaker: TrackEvent_Type.TYPE_SLICE_BEGIN,
+        defaultOrMaker: TrackEvent_Type.TYPE_UNSPECIFIED,
         valueOf: TrackEvent_Type.valueOf,
         enumValues: TrackEvent_Type.values)
     ..a<$fixnum.Int64>(

pkg/vm_service_protos/lib/src/protos/perfetto/trace/track_event/track_event.pbenum.dart

@@ -23,6 +23,9 @@ import 'package:protobuf/protobuf.dart' as $pb;
 
 /// Type of the TrackEvent (required if |phase| in LegacyEvent is not set).
 class TrackEvent_Type extends $pb.ProtobufEnum {
+  static const TrackEvent_Type TYPE_UNSPECIFIED =
+      TrackEvent_Type._(0, _omitEnumNames ? '' : 'TYPE_UNSPECIFIED');
+
   ///  Slice events are events that have a begin and end timestamp, i.e. a
   ///  duration. They can be nested similar to a callstack: If, on the same
   ///  track, event B begins after event A, but before A ends, B is a child
@@ -50,6 +53,7 @@ class TrackEvent_Type extends $pb.ProtobufEnum {
       TrackEvent_Type._(3, _omitEnumNames ? '' : 'TYPE_INSTANT');
 
   static const $core.List<TrackEvent_Type> values = <TrackEvent_Type>[
+    TYPE_UNSPECIFIED,
     TYPE_SLICE_BEGIN,
     TYPE_SLICE_END,
     TYPE_INSTANT,

pkg/vm_service_protos/lib/src/protos/perfetto/trace/track_event/track_event.pbjson.dart

@@ -63,6 +63,7 @@ const TrackEvent$json = {
 const TrackEvent_Type$json = {
   '1': 'Type',
   '2': [
+    {'1': 'TYPE_UNSPECIFIED', '2': 0},
     {'1': 'TYPE_SLICE_BEGIN', '2': 1},
     {'1': 'TYPE_SLICE_END', '2': 2},
     {'1': 'TYPE_INSTANT', '2': 3},
@@ -76,6 +77,6 @@ final $typed_data.Uint8List trackEventDescriptor = $convert.base64Decode(
     'eXBlUgR0eXBlEh0KCnRyYWNrX3V1aWQYCyABKARSCXRyYWNrVXVpZBIZCghmbG93X2lkcxgvIA'
     'MoBlIHZmxvd0lkcxIwChR0ZXJtaW5hdGluZ19mbG93X2lkcxgwIAMoBlISdGVybWluYXRpbmdG'
     'bG93SWRzEk0KEWRlYnVnX2Fubm90YXRpb25zGAQgAygLMiAucGVyZmV0dG8ucHJvdG9zLkRlYn'
-    'VnQW5ub3RhdGlvblIQZGVidWdBbm5vdGF0aW9ucyJCCgRUeXBlEhQKEFRZUEVfU0xJQ0VfQkVH'
-    'SU4QARISCg5UWVBFX1NMSUNFX0VORBACEhAKDFRZUEVfSU5TVEFOVBADQgwKCm5hbWVfZmllbG'
-    'Q=');
+    'VnQW5ub3RhdGlvblIQZGVidWdBbm5vdGF0aW9ucyJYCgRUeXBlEhQKEFRZUEVfVU5TUEVDSUZJ'
+    'RUQQABIUChBUWVBFX1NMSUNFX0JFR0lOEAESEgoOVFlQRV9TTElDRV9FTkQQAhIQCgxUWVBFX0'
+    'lOU1RBTlQQA0IMCgpuYW1lX2ZpZWxk');

runtime/vm/protos/perfetto/trace/track_event/track_event.pbzero.h

@@ -32,6 +32,7 @@ using TrackEvent_Type = perfetto_pbzero_enum_TrackEvent::Type;
 
 namespace perfetto_pbzero_enum_TrackEvent {
 enum Type : int32_t {
+  TYPE_UNSPECIFIED = 0,
   TYPE_SLICE_BEGIN = 1,
   TYPE_SLICE_END = 2,
   TYPE_INSTANT = 3,
@@ -40,13 +41,16 @@ enum Type : int32_t {
 using TrackEvent_Type = perfetto_pbzero_enum_TrackEvent::Type;
 
 constexpr TrackEvent_Type TrackEvent_Type_MIN =
-    TrackEvent_Type::TYPE_SLICE_BEGIN;
+    TrackEvent_Type::TYPE_UNSPECIFIED;
 constexpr TrackEvent_Type TrackEvent_Type_MAX = TrackEvent_Type::TYPE_INSTANT;
 
 PERFETTO_PROTOZERO_CONSTEXPR14_OR_INLINE
 const char* TrackEvent_Type_Name(
     ::perfetto::protos::pbzero::TrackEvent_Type value) {
   switch (value) {
+    case ::perfetto::protos::pbzero::TrackEvent_Type::TYPE_UNSPECIFIED:
+      return "TYPE_UNSPECIFIED";
+
     case ::perfetto::protos::pbzero::TrackEvent_Type::TYPE_SLICE_BEGIN:
       return "TYPE_SLICE_BEGIN";
 
@@ -116,6 +120,7 @@ class TrackEvent : public ::protozero::Message {
   static inline const char* Type_Name(Type value) {
     return ::perfetto::protos::pbzero::TrackEvent_Type_Name(value);
   }
+  static inline const Type TYPE_UNSPECIFIED = Type::TYPE_UNSPECIFIED;
   static inline const Type TYPE_SLICE_BEGIN = Type::TYPE_SLICE_BEGIN;
   static inline const Type TYPE_SLICE_END = Type::TYPE_SLICE_END;
   static inline const Type TYPE_INSTANT = Type::TYPE_INSTANT;

runtime/vm/protos/perfetto/trace/track_event/track_event.proto

@@ -112,6 +112,8 @@ message TrackEvent {
 
   // Type of the TrackEvent (required if |phase| in LegacyEvent is not set).
   enum Type {
+    TYPE_UNSPECIFIED = 0;
+
     // Slice events are events that have a begin and end timestamp, i.e. a
     // duration. They can be nested similar to a callstack: If, on the same
     // track, event B begins after event A, but before A ends, B is a child