fix broken windows build

chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc

Index: chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc
diff --git a/chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc b/chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc
index 32303856e716d7460771d6937fa07ce782d6d7f6..2d901c0cb7df2cd216d84a98706f42df42d70d5f 100644
--- a/chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc
+++ b/chrome/browser/ui/views/frame/app_panel_browser_frame_view.cc
@@ -107,6 +107,10 @@ AppPanelBrowserFrameView::GetTabStripInsets(bool restored) const {
   return TabStripInsets();
 }
 
+int AppPanelBrowserFrameView::GetThemeBackgroundXInset() const {
+  return 0;
+}
+
 void AppPanelBrowserFrameView::UpdateThrobber(bool running) {
   window_icon_->Update();
 }