Removes most aura dependencies from WindowResizer

ash/wm/aura/wm_root_window_controller_aura.cc

Index: ash/wm/aura/wm_root_window_controller_aura.cc
diff --git a/ash/wm/aura/wm_root_window_controller_aura.cc b/ash/wm/aura/wm_root_window_controller_aura.cc
index 812987591bacfe33a2b64bf21e0ca55aa3545353..ad249fe0136a57b92a236b8bc97624ad88d7d278 100644
--- a/ash/wm/aura/wm_root_window_controller_aura.cc
+++ b/ash/wm/aura/wm_root_window_controller_aura.cc
@@ -4,8 +4,11 @@
 
 #include "ash/wm/aura/wm_root_window_controller_aura.h"
 
+#include "ash/display/window_tree_host_manager.h"
 #include "ash/root_window_controller.h"
+#include "ash/shell.h"
 #include "ash/wm/aura/wm_globals_aura.h"
+#include "ash/wm/aura/wm_window_aura.h"
 #include "ash/wm/workspace_controller.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_property.h"
@@ -20,6 +23,13 @@ DEFINE_OWNED_WINDOW_PROPERTY_KEY(ash::wm::WmRootWindowControllerAura,
                                  kWmRootWindowControllerKey,
                                  nullptr);
 
+// static
+WmRootWindowController* WmRootWindowController::GetWithDisplayId(int64_t id) {
+  return WmRootWindowControllerAura::Get(Shell::GetInstance()
+                                             ->window_tree_host_manager()
+                                             ->GetRootWindowForDisplayId(id));
+}
+
 WmRootWindowControllerAura::WmRootWindowControllerAura(
     RootWindowController* root_window_controller)
     : root_window_controller_(root_window_controller) {
@@ -62,5 +72,9 @@ WorkspaceWindowState WmRootWindowControllerAura::GetWorkspaceWindowState() {
   return root_window_controller_->workspace_controller()->GetWindowState();
 }
 
+WmWindow* WmRootWindowControllerAura::GetWindow() {
+  return WmWindowAura::Get(root_window_controller_->GetRootWindow());
+}
+
 }  // namespace wm
 }  // namespace ash