linux_aura: Three fixes for switching themes.

ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc

Index: ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc
diff --git a/ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc b/ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc
index ea98a9cdacbb64f2b10aa4539666c6b8286af6a0..78d3e9de737d6983d2974d6a03de96c5e28ffe31 100644
--- a/ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc
+++ b/ui/views/widget/desktop_aura/desktop_root_window_host_x11.cc
@@ -619,6 +619,10 @@ bool DesktopRootWindowHostX11::ShouldUseNativeFrame() {
 }
 
 void DesktopRootWindowHostX11::FrameTypeChanged() {
+  // Replace the frame and layout the contents. Even though we don't have a
+  // swapable glass frame like on Windows, we still replace the frame because
+  // the button assets don't update otherwise.
+  native_widget_delegate_->AsWidget()->non_client_view()->UpdateFrame(true);
 }
 
 NonClientFrameView* DesktopRootWindowHostX11::CreateNonClientFrameView() {