Implement WebContentsModalDialogManagerDelegate for ShellWindow

chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm

Index: chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm b/chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm
index fcd4a15f3ed795a610d864dabdc2f5ea80ba5af2..21dbb2dcc779fd98077ae656178f95ebeaa4dc72 100644
--- a/chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/extensions/native_app_window_cocoa.mm
@@ -693,6 +693,21 @@ gfx::Insets NativeAppWindowCocoa::GetFrameInsets() const {
   return frame_rect.InsetsFrom(content_rect);
 }
 
+gfx::Point NativeAppWindowCocoa::GetDialogPosition(const gfx::Size& size) {
+  NOTIMPLEMENTED();
+  return gfx::Point();
+}
+
+void NativeAppWindowCocoa::AddObserver(
+    WebContentsModalDialogHostObserver* observer) {
+  NOTIMPLEMENTED();
+}
+
+void NativeAppWindowCocoa::RemoveObserver(
+    WebContentsModalDialogHostObserver* observer) {
+  NOTIMPLEMENTED();
+}
+
 void NativeAppWindowCocoa::WindowWillClose() {
   [window_controller_ setAppWindow:NULL];
   shell_window_->OnNativeWindowChanged();