Bug 1646266 - ProfileBufferEntryKind::Marker - r=gregtatum

A new entry kind is needed to serialize the new markers, because they are not encoded the same way.

Differential Revision: https://phabricator.services.mozilla.com/D87253

mozglue/baseprofiler/public/ProfileBufferEntryKinds.h

@@ -73,6 +73,9 @@ enum class ProfileBufferEntryKind : ProfileBufferEntryKindUnderlyingType {
   // Marker data, including payload.
   MarkerData = LEGACY_LIMIT,
 
+  // Markers from 2.0 specs.
+  Marker,
+
   // Optional between TimeBeforeCompactStack and CompactStack.
   UnresponsiveDurationMs,