Make GetRootWindow() return a Window instead of a RootWindow.

chrome/browser/ui/ash/screenshot_taker.cc

Index: chrome/browser/ui/ash/screenshot_taker.cc
diff --git a/chrome/browser/ui/ash/screenshot_taker.cc b/chrome/browser/ui/ash/screenshot_taker.cc
index b7517f27eb4e2679ebbce5f04072044dd7dce74c..adaee4e832c50dff15fcbe0466d2b75f7dc91007 100644
--- a/chrome/browser/ui/ash/screenshot_taker.cc
+++ b/chrome/browser/ui/ash/screenshot_taker.cc
@@ -343,11 +343,11 @@ void ScreenshotTaker::HandleTakeScreenshotForAllRootWindows() {
 
   ash::Shell::RootWindowList root_windows = ash::Shell::GetAllRootWindows();
   // Reorder root_windows to take the primary root window's snapshot at first.
-  aura::RootWindow* primary_root = ash::Shell::GetPrimaryRootWindow();
+  aura::Window* primary_root = ash::Shell::GetPrimaryRootWindow();
   if (*(root_windows.begin()) != primary_root) {
     root_windows.erase(std::find(
         root_windows.begin(), root_windows.end(), primary_root));
-    root_windows.insert(root_windows.begin(), primary_root);
+    root_windows.insert(root_windows.begin(), primary_root->GetDispatcher());
   }
   for (size_t i = 0; i < root_windows.size(); ++i) {
     aura::RootWindow* root_window = root_windows[i];