Linux UI: Add IsVisibleOnAllWorkspaces()

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 2bb3b4bcd7a704e48796f7a5cd5b57d731efe1ee..4296fc11036e5e409b7bfcb4a44daeb3810b2962 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
@@ -715,6 +715,7 @@ void DesktopWindowTreeHostX11::SetVisibleOnAllWorkspaces(bool always_visible) {
       return;
   }
 
+  workspace_ = base::IntToString(kAllDesktops);
   XEvent xevent;
   memset (&xevent, 0, sizeof (xevent));
   xevent.type = ClientMessage;
@@ -731,6 +732,14 @@ void DesktopWindowTreeHostX11::SetVisibleOnAllWorkspaces(bool always_visible) {
              &xevent);
 }
 
+bool DesktopWindowTreeHostX11::IsVisibleOnAllWorkspaces() const {
+  // We don't need a check for _NET_WM_STATE_STICKY because that would specify
+  // that the window remain in a fixed position even if the viewport scrolls.
+  // This is different from the type of workspace that's associated with
+  // _NET_WM_DESKTOP.
+  return GetWorkspace() == base::IntToString(kAllDesktops);
+}
+
 bool DesktopWindowTreeHostX11::SetWindowTitle(const base::string16& title) {
   if (window_title_ == title)
     return false;