Replace HeapListHashSet with HeapLinkedHashSet in (autogen) CoreProbeSink

HeapListHashSet is deprecated in favor of HeapLinkedHashSet.

HeapLinkedHashSet's invalidate iterators when the container is
modified. It happens here that CoreProbeSink::Remove{{class_name}}
(which calls HeapLinkedHashSet<{{class_name}}>::erase) can be called
while iterating over probe_sink->{{class_name}}s(). Hence, a helper
function was added in order to perform the copy.

Note that having a helper function rather than the copy code inlined
helps with binary size matters.

R=jbroman@chromium.org
CC=​​blink-reviews-vendor@chromium.org

BUG=614112

Change-Id: I25692b867e0c32dc634b7d7f3a84877218082268
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1584109Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Antonio Gomes <tonikitoo@igalia.com>
Cr-Commit-Position: refs/heads/master@{#654540}

third_party/blink/renderer/build/scripts/templates/instrumenting_probes_impl.cc.tmpl

@@ -25,6 +25,19 @@ Mutex& AgentCountMutex() {
   return mutex;
 }
 
+// HeapLinkedHashSet does not support modification during iteration.
+// This helper copies items first so calees iterate over the copied container.
+template <typename T>
+HeapVector<Member<T>> CopyLinkedHashSetToVector(
+    const HeapLinkedHashSet<Member<T>>& linked_hash_set) {
+  unsigned capacity = linked_hash_set.size();
+  HeapVector<Member<T>> result;
+  result.ReserveInitialCapacity(capacity);
+  for (T* agent : linked_hash_set)
+      result.push_back(agent);
+  return result;
+}
+
 }  // namespace
 
 // static
@@ -101,7 +114,8 @@ namespace probe {
 {% for agent in probe.agents %}
 {% set class_name = agent | agent_name_to_class %}
   if (probe_sink->Has{{agent}}s()) {
-    for ({{class_name}}* agent : probe_sink->{{class_name}}s())
+    auto copy = CopyLinkedHashSetToVector(probe_sink->{{class_name}}s());
+    for ({{class_name}}* agent : copy)
       agent->{{agent_probe_name}}({{caller()}});
   }
 {% endfor %}

third_party/blink/renderer/build/scripts/templates/probe_sink.h.tmpl

@@ -43,7 +43,7 @@ class {{export_symbol}} {{sink_class}} : public GarbageCollectedFinalized<{{sink
 {% set class_name = agent | agent_name_to_class %}
 {% set getter_name = agent | to_snake_case %}
   bool Has{{agent}}s() const { return !{{getter_name}}s_.IsEmpty(); }
-  const HeapListHashSet<Member<{{class_name}}>>& {{class_name}}s() const { return {{getter_name}}s_; }
+  const HeapLinkedHashSet<Member<{{class_name}}>>& {{class_name}}s() const { return {{getter_name}}s_; }
   void Add{{agent}}({{class_name}}* agent);
   void Remove{{agent}}({{class_name}}* agent);
 
@@ -57,7 +57,7 @@ class {{export_symbol}} {{sink_class}} : public GarbageCollectedFinalized<{{sink
 {% for agent in agents %}
 {% set class_name = agent | agent_name_to_class %}
 {% set getter_name = agent | to_snake_case %}
-  HeapListHashSet<Member<{{class_name}}>> {{getter_name}}s_;
+  HeapLinkedHashSet<Member<{{class_name}}>> {{getter_name}}s_;
 {% endfor %}
 
   // Number of sinks with an enabled agent of each type, used to keep