Add Tracing.requestMemoryDump method stub to DevTools API

content/browser/devtools/protocol/tracing_handler.cc

Index: content/browser/devtools/protocol/tracing_handler.cc
diff --git a/content/browser/devtools/protocol/tracing_handler.cc b/content/browser/devtools/protocol/tracing_handler.cc
index f616c5e00c9cf2786e1cdce717a2d7b44fa4defa..d3611b352c36b19a049eb67c24ee025fe9fe1812 100644
--- a/content/browser/devtools/protocol/tracing_handler.cc
+++ b/content/browser/devtools/protocol/tracing_handler.cc
@@ -153,6 +153,10 @@ void TracingHandler::OnCategoriesReceived(
       GetCategoriesResponse::Create()->set_categories(categories));
 }
 
+Response TracingHandler::RequestMemoryDump(DevToolsCommandId command_id) {
+  return Response::InternalError("Not implemented");
+}
+
 void TracingHandler::SetupTimer(double usage_reporting_interval) {
   if (usage_reporting_interval == 0) return;