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

components/ui_devtools/BUILD.gn

Index: components/ui_devtools/BUILD.gn
diff --git a/components/ui_devtools/BUILD.gn b/components/ui_devtools/BUILD.gn
index eab5c09cbf97716c66fabef18e846737e6bea9d1..e2770282aa3d02161a48c89f1d2b298224f5b429 100644
--- a/components/ui_devtools/BUILD.gn
+++ b/components/ui_devtools/BUILD.gn
@@ -4,6 +4,7 @@
 
 _inspector_protocol = "//third_party/inspector_protocol"
 import("$_inspector_protocol/inspector_protocol.gni")
+import("//testing/test.gni")
 
 _protocol_generated = [
   "CSS.cpp",
@@ -55,6 +56,19 @@ inspector_protocol_generate("protocol_generated_sources") {
 source_set("ui_devtools") {
   sources = rebase_path(_protocol_generated, ".", target_gen_dir)
   sources += [
+    "devtools/ui_devtools_css_agent.cc",
+    "devtools/ui_devtools_css_agent.h",
+    "devtools/ui_devtools_dom_agent.cc",
+    "devtools/ui_devtools_dom_agent.h",
+    "devtools/ui_element.cc",
+    "devtools/ui_element.h",
+    "devtools/ui_element_delegate.h",
+    "devtools/view_element.cc",
+    "devtools/view_element.h",
+    "devtools/widget_element.cc",
+    "devtools/widget_element.h",
+    "devtools/window_element.cc",
+    "devtools/window_element.h",
     "devtools_base_agent.h",
     "devtools_client.cc",
     "devtools_client.h",
@@ -76,8 +90,30 @@ source_set("ui_devtools") {
 
   deps = [
     ":protocol_generated_sources",
+    "//ash/public/cpp:ash_public_cpp",
     "//base",
     "//net",
     "//net:http_server",
+    "//skia",
+    "//ui/aura",
+    "//ui/views",
+    "//ui/wm:wm",
+  ]
+}
+
+source_set("devtool_unittests") {
+  testonly = true
+  sources = [
+    "devtools/ui_devtools_unittest.cc",
+  ]
+  configs += [ "//build/config:precompiled_headers" ]
+  deps = [
+    ":ui_devtools",
+    "//ash/public/cpp:ash_public_cpp",
+    "//skia",
+    "//testing/gtest",
+    "//ui/aura",
+    "//ui/views",
+    "//ui/wm:wm",
   ]
 }