EventListener does not project GCPerHeapHistory_V3 values array

The [GCPerHeapHistory_V3 event](https://github.com/dotnet/runtime/blob/master/src/coreclr/src/vm/ClrEtwAll.man#L1166) has an array called 'Values'. This array of structs should be projected into the EventListener event model but it is absent. Most likely this is a broader issue handling array typed fields, or perhaps dynamically sized array-typed fields.

Repro:
````C#
using System;
using System.Collections.Generic;
using System.Diagnostics.Tracing;
using System.Threading;
using System.Threading.Tasks;

namespace ConsoleApp19
{
class Program
{
static List s_objects = new List();

static void Main(string[] args)
{
GCEventListener listener = new GCEventListener();
Task.Run(AllocateMemory);
Console.ReadLine();
}

static void AllocateMemory()
{
while (true)
{
s_objects.Add(new byte[50_000]);
Thread.Sleep(10);
}
}
}

public class GCEventListener : EventListener
{
enum ClrRuntimeEventKeywords
{
GC = 0x1
}

protected override void OnEventSourceCreated(EventSource eventSource)
{
if (eventSource.Name.Equals("Microsoft-Windows-DotNETRuntime"))
{
EnableEvents(eventSource, EventLevel.Informational, (EventKeywords)ClrRuntimeEventKeywords.GC);
}
}
protected override void OnEventWritten(EventWrittenEventArgs eventData)
{
if (eventData.EventName == "GCPerHeapHistory_V3")
{
Console.WriteLine(eventData.EventName);
foreach (string name in eventData.PayloadNames)
{
Console.WriteLine(" " + name);
}
}
}
}
}
````

**Expected behavior**: this app should print a payload field named "Values" in addition to the others
(and assuming that works you should be able to retrieve the array and access the nested fields)
**Actual behavior**: the app prints over payload fields, but not "Values"