view-manager: Fix some issues regarding running tests in x11.

ui/platform_window/x11/x11_window.cc

Index: ui/platform_window/x11/x11_window.cc
diff --git a/ui/platform_window/x11/x11_window.cc b/ui/platform_window/x11/x11_window.cc
index 1e94ae2e27f1adf38b1a17fa20c65c421a1fe977..82be0f43e3cb87d8022978d9f90994e7ecfdb361 100644
--- a/ui/platform_window/x11/x11_window.cc
+++ b/ui/platform_window/x11/x11_window.cc
@@ -200,9 +200,6 @@ void X11Window::Show() {
   size_hints.win_gravity = StaticGravity;
   XSetWMNormalHints(xdisplay_, xwindow_, &size_hints);
 
-  // TODO(sky): provide real scale factor.
-  delegate_->OnAcceleratedWidgetAvailable(xwindow_, 1.f);
-
   XMapWindow(xdisplay_, xwindow_);
 
   // We now block until our window is mapped. Some X11 APIs will crash and
@@ -211,6 +208,9 @@ void X11Window::Show() {
   if (X11EventSource::GetInstance())
     X11EventSource::GetInstance()->BlockUntilWindowMapped(xwindow_);
   window_mapped_ = true;
+
+  // TODO(sky): provide real scale factor.
+  delegate_->OnAcceleratedWidgetAvailable(xwindow_, 1.f);
 }
 
 void X11Window::Hide() {