mash: Move directly linked NewWindowDelegate to mojom::NewWindowClient.

ash/common/shell_delegate.h

Index: ash/common/shell_delegate.h
diff --git a/ash/common/shell_delegate.h b/ash/common/shell_delegate.h
index f928628fa785d4804b085327712d74d923190482..e36fe616c46f152ca500406c206ebdbf1f29fdf1 100644
--- a/ash/common/shell_delegate.h
+++ b/ash/common/shell_delegate.h
@@ -44,7 +44,6 @@ namespace ash {
 class AccessibilityDelegate;
 class GPUSupport;
 class MediaDelegate;
-class NewWindowDelegate;
 class PaletteDelegate;
 class SessionStateDelegate;
 class ShelfDelegate;
@@ -119,9 +118,6 @@ class ASH_EXPORT ShellDelegate {
   // Creates a accessibility delegate. Shell takes ownership of the delegate.
   virtual AccessibilityDelegate* CreateAccessibilityDelegate() = 0;
 
-  // Creates an application delegate. Shell takes ownership of the delegate.
-  virtual NewWindowDelegate* CreateNewWindowDelegate() = 0;
-
   // Creates a media delegate. Shell takes ownership of the delegate.
   virtual MediaDelegate* CreateMediaDelegate() = 0;