DevTools: provide an option to return traces as streams

content/browser/devtools/render_frame_devtools_agent_host.cc

Index: content/browser/devtools/render_frame_devtools_agent_host.cc
diff --git a/content/browser/devtools/render_frame_devtools_agent_host.cc b/content/browser/devtools/render_frame_devtools_agent_host.cc
index 627d32db44b255d4ce09313856ff893871b95304..2c8ac8f84445f33ea9db2ff162ac33ff452dbd4c 100644
--- a/content/browser/devtools/render_frame_devtools_agent_host.cc
+++ b/content/browser/devtools/render_frame_devtools_agent_host.cc
@@ -14,6 +14,7 @@
 #include "content/browser/devtools/protocol/emulation_handler.h"
 #include "content/browser/devtools/protocol/input_handler.h"
 #include "content/browser/devtools/protocol/inspector_handler.h"
+#include "content/browser/devtools/protocol/io_handler.h"
 #include "content/browser/devtools/protocol/network_handler.h"
 #include "content/browser/devtools/protocol/page_handler.h"
 #include "content/browser/devtools/protocol/power_handler.h"
@@ -293,6 +294,7 @@ RenderFrameDevToolsAgentHost::RenderFrameDevToolsAgentHost(
     : dom_handler_(new devtools::dom::DOMHandler()),
       input_handler_(new devtools::input::InputHandler()),
       inspector_handler_(new devtools::inspector::InspectorHandler()),
+      io_handler_(new devtools::io::IOHandler(GetIOContext())),
       network_handler_(new devtools::network::NetworkHandler()),
       page_handler_(nullptr),
       power_handler_(new devtools::power::PowerHandler()),
@@ -300,7 +302,8 @@ RenderFrameDevToolsAgentHost::RenderFrameDevToolsAgentHost(
       service_worker_handler_(
           new devtools::service_worker::ServiceWorkerHandler()),
       tracing_handler_(new devtools::tracing::TracingHandler(
-          devtools::tracing::TracingHandler::Renderer)),
+          devtools::tracing::TracingHandler::Renderer,
+          GetIOContext())),
       emulation_handler_(nullptr),
       frame_trace_recorder_(nullptr),
       protocol_handler_(new DevToolsProtocolHandler(