Remove ash dependency.

ash/devtools/ash_devtools_dom_agent.cc

Index: ash/devtools/ash_devtools_dom_agent.cc
diff --git a/ash/devtools/ash_devtools_dom_agent.cc b/ash/devtools/ash_devtools_dom_agent.cc
index 3a6831a8e2e25ea8073ea354302fe3a99dd1cda3..ce290b5e49e1e0a577e598ec162d5872321cead4 100644
--- a/ash/devtools/ash_devtools_dom_agent.cc
+++ b/ash/devtools/ash_devtools_dom_agent.cc
@@ -9,12 +9,14 @@
 #include "ash/devtools/widget_element.h"
 #include "ash/devtools/window_element.h"
 #include "ash/public/cpp/shell_window_ids.h"
-#include "ash/root_window_controller.h"
-#include "ash/shell.h"
 #include "components/ui_devtools/devtools_server.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "ui/aura/client/screen_position_client.h"
+#include "ui/aura/env.h"
 #include "ui/aura/window.h"
+#include "ui/aura/window_tree_host.h"
 #include "ui/display/display.h"
+#include "ui/display/screen.h"
 #include "ui/views/background.h"
 #include "ui/views/border.h"
 #include "ui/views/view.h"
@@ -116,9 +118,12 @@ std::unique_ptr<DOM::Node> BuildDomNodeFromUIElement(UIElement* root) {
 
 }  // namespace
 
-AshDevToolsDOMAgent::AshDevToolsDOMAgent() : is_building_tree_(false) {}
+AshDevToolsDOMAgent::AshDevToolsDOMAgent() : is_building_tree_(false) {
+  aura::Env::GetInstance()->AddObserver(this);
+}
 
 AshDevToolsDOMAgent::~AshDevToolsDOMAgent() {
+  aura::Env::GetInstance()->RemoveObserver(this);
   Reset();
 }
 
@@ -209,6 +214,10 @@ UIElement* AshDevToolsDOMAgent::GetElementFromNodeId(int node_id) {
   return node_id_to_ui_element_[node_id];
 }
 
+void AshDevToolsDOMAgent::OnHostInitialized(aura::WindowTreeHost* host) {
+  root_windows_.push_back(host->window());
+}
+
 void AshDevToolsDOMAgent::OnNodeBoundsChanged(int node_id) {
   for (auto& observer : observers_)
     observer.OnNodeBoundsChanged(node_id);
@@ -224,7 +233,7 @@ AshDevToolsDOMAgent::BuildInitialTree() {
   window_element_root_ =
       base::MakeUnique<WindowElement>(nullptr, this, nullptr);
 
-  for (aura::Window* window : Shell::GetAllRootWindows()) {
+  for (aura::Window* window : root_windows()) {
     UIElement* window_element =
         new WindowElement(window, this, window_element_root_.get());
 
@@ -338,10 +347,6 @@ void AshDevToolsDOMAgent::InitializeHighlightingWidget() {
   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
   params.opacity = views::Widget::InitParams::WindowOpacity::TRANSLUCENT_WINDOW;
   params.name = "HighlightingWidget";
-  Shell::GetPrimaryRootWindowController()
-      ->ConfigureWidgetInitParamsForContainer(widget_for_highlighting_.get(),
-                                              kShellWindowId_OverlayContainer,
-                                              &params);
   params.keep_on_top = true;
   params.accept_events = false;
   widget_for_highlighting_->Init(params);
@@ -359,8 +364,18 @@ void AshDevToolsDOMAgent::UpdateHighlight(
   display::Display display =
       display::Screen::GetScreen()->GetDisplayNearestWindow(
           window_and_bounds.first);
-  widget_for_highlighting_->GetNativeWindow()->SetBoundsInScreen(
-      window_and_bounds.second, display);
+  aura::Window* root = window_and_bounds.first->GetRootWindow();
+  if (root != widget_for_highlighting_->GetNativeWindow()->GetRootWindow())
+    root->AddChild(widget_for_highlighting_->GetNativeWindow());
+
+  aura::client::ScreenPositionClient* screen_position_client =
+      aura::client::GetScreenPositionClient(root);
+
+  gfx::Rect bounds(window_and_bounds.second);
+  gfx::Point origin = bounds.origin();
+  screen_position_client->ConvertPointFromScreen(root, &origin);
+  bounds.set_origin(origin);
+  widget_for_highlighting_->GetNativeWindow()->SetBounds(bounds);
 }
 
 ui::devtools::protocol::Response AshDevToolsDOMAgent::HighlightNode(