DevTools: introduce browser domain for basic target discovery.

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 3467a03fa8a5214c55f9aebec4ff7350859b77f3..07f422484bb4e4033b7e1bffc7c33b6b134f7430 100644
--- a/content/browser/devtools/render_frame_devtools_agent_host.cc
+++ b/content/browser/devtools/render_frame_devtools_agent_host.cc
@@ -13,6 +13,7 @@
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/devtools/devtools_frame_trace_recorder.h"
 #include "content/browser/devtools/devtools_protocol_handler.h"
+#include "content/browser/devtools/protocol/browser_handler.h"
 #include "content/browser/devtools/protocol/dom_handler.h"
 #include "content/browser/devtools/protocol/emulation_handler.h"
 #include "content/browser/devtools/protocol/input_handler.h"
@@ -347,7 +348,8 @@ void RenderFrameDevToolsAgentHost::OnBeforeNavigation(
 
 RenderFrameDevToolsAgentHost::RenderFrameDevToolsAgentHost(
     RenderFrameHostImpl* host)
-    : dom_handler_(new devtools::dom::DOMHandler()),
+    : browser_handler_(new devtools::browser::BrowserHandler()),
+      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())),
@@ -368,6 +370,7 @@ RenderFrameDevToolsAgentHost::RenderFrameDevToolsAgentHost(
       pending_handle_(nullptr),
       frame_tree_node_(host->frame_tree_node()) {
   DevToolsProtocolDispatcher* dispatcher = protocol_handler_->dispatcher();
+  dispatcher->SetBrowserHandler(browser_handler_.get());
   dispatcher->SetDOMHandler(dom_handler_.get());
   dispatcher->SetInputHandler(input_handler_.get());
   dispatcher->SetInspectorHandler(inspector_handler_.get());