add a new set of commands to resize and position windows

content/browser/devtools/browser_devtools_agent_host.cc

Index: content/browser/devtools/browser_devtools_agent_host.cc
diff --git a/content/browser/devtools/browser_devtools_agent_host.cc b/content/browser/devtools/browser_devtools_agent_host.cc
index 0d04330f8604b68031c7b6c36ac89be0d2e05e4e..3d5c161d8ac6b70d14cd91c43e9cf5a9d7a38438 100644
--- a/content/browser/devtools/browser_devtools_agent_host.cc
+++ b/content/browser/devtools/browser_devtools_agent_host.cc
@@ -15,6 +15,7 @@
 #include "content/browser/devtools/protocol/target_handler.h"
 #include "content/browser/devtools/protocol/tethering_handler.h"
 #include "content/browser/devtools/protocol/tracing_handler.h"
+#include "content/browser/devtools/protocol/ui_handler.h"
 #include "content/browser/frame_host/frame_tree_node.h"
 
 namespace content {
@@ -61,6 +62,7 @@ void BrowserDevToolsAgentHost::AttachSession(DevToolsSession* session) {
       protocol::TracingHandler::Browser,
       FrameTreeNode::kFrameTreeNodeInvalidId,
       GetIOContext())));
+  session->AddHandler(base::WrapUnique(new protocol::UIHandler()));
 }
 
 void BrowserDevToolsAgentHost::DetachSession(int session_id) {