Aura/ash split: Remove hacks and get chrome linking without ash.

ash/shell/content_client/shell_browser_main_parts.cc

Index: ash/shell/content_client/shell_browser_main_parts.cc
diff --git a/ash/shell/content_client/shell_browser_main_parts.cc b/ash/shell/content_client/shell_browser_main_parts.cc
index 2aaaed2be8c148fd5059b12f22847ac871598467..0d4a1a51f0a69ee0775a4b83e6269d9647c9b281 100644
--- a/ash/shell/content_client/shell_browser_main_parts.cc
+++ b/ash/shell/content_client/shell_browser_main_parts.cc
@@ -52,6 +52,13 @@ class ShellViewsDelegate : public views::TestViewsDelegate {
     return true;
   }
 
+  views::NativeWidgetHelperAura* CreateNativeWidgetHelper(
+      views::NativeWidgetAura* native_widget) OVERRIDE {
+    // The default behavior of the test delegate is to work in desktop
+    // mode. Return NULL here so NativeWidgetAura uses our RootWindow instead.
+    return NULL;
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ShellViewsDelegate);
 };