Add WindowPinType property on arua::Window

ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc

Index: ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
index fd25fc60ae0bd0331902c8d0ece1610699c563d1..0f0764ce6c1a38ea70e8376ff4f62d1ed1445f6d 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
@@ -345,6 +345,12 @@ void DesktopWindowTreeHostWin::Minimize() {
   message_handler_->Minimize();
 }
 
+void DesktopWindowTreeHostWin::Pin(bool trusted) {
+  // We only use Pin() for ARC++ window on Chromebook, so we don't need
+  // implement it for Windows.
+  NOTIMPLEMENTED();
+}
+
 void DesktopWindowTreeHostWin::Restore() {
   message_handler_->Restore();
 }
@@ -357,6 +363,10 @@ bool DesktopWindowTreeHostWin::IsMinimized() const {
   return message_handler_->IsMinimized();
 }
 
+bool DesktopWindowTreeHostWin::IsPinned() const {
+  return false;
+}
+
 bool DesktopWindowTreeHostWin::HasCapture() const {
   return message_handler_->HasCapture();
 }