Merge three implementations for getting the topmost x11 window at a point

ui/views/widget/desktop_aura/desktop_screen_x11.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/widget/desktop_aura/desktop_screen_x11.h"
 
 #include <X11/extensions/Xrandr.h>
 #include <X11/Xlib.h>
 
 // It clashes with out RootWindow.
 #undef RootWindow
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/base/layout.h"
 #include "ui/display/util/display_util.h"
 #include "ui/display/util/x11/edid_parser_x11.h"
 #include "ui/events/platform/platform_event_source.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/display_observer.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/screen.h"
 #include "ui/gfx/x/x11_types.h"
 #include "ui/views/widget/desktop_aura/desktop_screen.h"
 #include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
+#include "ui/views/widget/desktop_aura/x11_topmost_window_finder.h"
 
 namespace {
 
 // The delay to perform configuration after RRNotify.  See the comment
 // in |Dispatch()|.
 const int64 kConfigureDelayMs = 500;
 
 float GetDeviceScaleFactor(int screen_pixels, int screen_mm) {
   const int kCSSDefaultDPI = 96;
   const float kInchInMm = 25.4f;
@@ skipping 18 matching lines @@
       !ui::IsDisplaySizeBlackListed(physical_size)) {
     float device_scale_factor = GetDeviceScaleFactor(
         width, physical_size.width());
     DCHECK_LE(1.0f, device_scale_factor);
     gfx_display.SetScaleAndBounds(device_scale_factor, bounds_in_pixels);
   }
 
   return std::vector<gfx::Display>(1, gfx_display);
 }
 
-// Helper class to GetWindowAtScreenPoint() which returns the topmost window at
-// the location passed to FindAt(). NULL is returned if a window which does not
-// belong to Chromium is topmost at the passed in location.
-class ToplevelWindowFinder : public ui::EnumerateWindowsDelegate {
- public:
-  ToplevelWindowFinder() : toplevel_(NULL) {
-  }
-
-  virtual ~ToplevelWindowFinder() {
-  }
-
-  aura::Window* FindAt(const gfx::Point& screen_loc) {
-    screen_loc_ = screen_loc;
-    ui::EnumerateTopLevelWindows(this);
-    return toplevel_;
-  }
-
- protected:
-  virtual bool ShouldStopIterating(XID xid) OVERRIDE {
-   if (!ui::IsWindowVisible(xid))
-     return false;
-
-    aura::Window* window =
-        views::DesktopWindowTreeHostX11::GetContentWindowForXID(xid);
-    if (window) {
-      // Currently |window|->IsVisible() always returns true.
-      // TODO(pkotwicz): Fix this. crbug.com/353038
-      if (window->IsVisible() &&
-          window->GetBoundsInScreen().Contains(screen_loc_)) {
-        toplevel_ = window;
-        return true;
-      }
-      return false;
-    }
-
-    if (ui::WindowContainsPoint(xid, screen_loc_)) {
-      // toplevel_ = NULL
-      return true;
-    }
-    return false;
-  }
-
-  gfx::Point screen_loc_;
-  aura::Window* toplevel_;
-
-  DISALLOW_COPY_AND_ASSIGN(ToplevelWindowFinder);
-};
-
 }  // namespace
 
 namespace views {
 
 ////////////////////////////////////////////////////////////////////////////////
 // DesktopScreenX11, public:
 
 DesktopScreenX11::DesktopScreenX11()
     : xdisplay_(gfx::GetXDisplay()),
       x_root_window_(DefaultRootWindow(xdisplay_)),
@@ skipping 104 matching lines @@
 
   return gfx::Point(root_x, root_y);
 }
 
 gfx::NativeWindow DesktopScreenX11::GetWindowUnderCursor() {
   return GetWindowAtScreenPoint(GetCursorScreenPoint());
 }
 
 gfx::NativeWindow DesktopScreenX11::GetWindowAtScreenPoint(
     const gfx::Point& point) {
-  ToplevelWindowFinder finder;
-  return finder.FindAt(point);
+  X11TopmostWindowFinder finder;
+  return finder.FindLocalProcessWindowAt(point, std::set<aura::Window*>());
 }
 
 int DesktopScreenX11::GetNumDisplays() const {
   return displays_.size();
 }
 
 std::vector<gfx::Display> DesktopScreenX11::GetAllDisplays() const {
   return displays_;
 }
 
@@ skipping 184 matching lines @@
   ProcessDisplayChange(new_displays);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 gfx::Screen* CreateDesktopScreen() {
   return new DesktopScreenX11;
 }
 
 }  // namespace views