Fix missing shadows for tooltip and menu

ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc

Index: ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
index aeadc78f2fe40a9863c39daa451852a86f78cf9f..3f96e65ed1cc15704ec15ffacdc52553403db7b7 100644
--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
+++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
@@ -1156,23 +1156,29 @@ void DesktopWindowTreeHostX11::InitX11Window(
   if (swa.override_redirect)
     attribute_mask |= CWOverrideRedirect;
 
-  Visual* visual;
-  int depth;
-  ui::ChooseVisualForWindow(true, &visual, &depth);
-  if (depth == 32) {
-    attribute_mask |= CWColormap;
-    swa.colormap =
-        XCreateColormap(xdisplay_, x_root_window_, visual, AllocNone);
-
-    // x.org will BadMatch if we don't set a border when the depth isn't the
-    // same as the parent depth.
-    attribute_mask |= CWBorderPixel;
-    swa.border_pixel = 0;
-
-    // A compositing manager is required to support transparency.
-    use_argb_visual_ =
-        XGetSelectionOwner(xdisplay_, atom_cache_.GetAtom("_NET_WM_CM_S0")) !=
-        None;
+  bool enable_transparent_visuals =
+      params.type == Widget::InitParams::TYPE_DRAG ||
+      params.type == Widget::InitParams::TYPE_WINDOW;
+
+  Visual* visual = CopyFromParent;
+  int depth = CopyFromParent;
+  if (enable_transparent_visuals) {
+    ui::ChooseVisualForWindow(enable_transparent_visuals, &visual, &depth);

[piman, 2016/08/24 17:21:49]

Ignoring the statics for a second, ChooseVisualForWindow would return the root
window's (i.e. the parent's) visual if enable_transparent_visuals is false.

So, could we fix ChooseVisualForWindow to cache separately the visuals for
transparent and opaque? I think it would make more sense: ChooseVisualForWindow
would choose the right visual based on enable_transparent_visuals, independent
of how it was called before. That way, we don't need to distribute the logic
between there and here.

+    if (depth == 32) {
+      attribute_mask |= CWColormap;
+      swa.colormap =
+          XCreateColormap(xdisplay_, x_root_window_, visual, AllocNone);
+
+      // x.org will BadMatch if we don't set a border when the depth isn't the
+      // same as the parent depth.
+      attribute_mask |= CWBorderPixel;
+      swa.border_pixel = 0;
+
+      // A compositing manager is required to support transparency.
+      use_argb_visual_ =
+          XGetSelectionOwner(xdisplay_, atom_cache_.GetAtom("_NET_WM_CM_S0")) !=
+          None;
+    }
   }
 
   bounds_in_pixels_ = ToPixelRect(params.bounds);