Move DevTools out of ash and turn it to a component.

components/ui_devtools/devtools_server.cc

Index: components/ui_devtools/devtools_server.cc
diff --git a/components/ui_devtools/devtools_server.cc b/components/ui_devtools/devtools_server.cc
index fd0e35b93d5ac3acfd828899242d6d7db89bc33a..c8fd76c15f1bbb4aa29ed94ce537c75446a43eb1 100644
--- a/components/ui_devtools/devtools_server.cc
+++ b/components/ui_devtools/devtools_server.cc
@@ -21,8 +21,7 @@
 #include "net/socket/server_socket.h"
 #include "net/socket/tcp_server_socket.h"
 
-namespace ui {
-namespace devtools {
+namespace ui_devtools {
 
 namespace {
 const char kChromeDeveloperToolsPrefix[] =
@@ -182,5 +181,4 @@ void UiDevToolsServer::OnClose(int connection_id) {
   connections_.erase(it);
 }
 
-}  // namespace devtools
-}  // namespace ui
+}  // namespace ui_devtools