Ozone and X11: Use TopMostWindowFinder through display::Screen

display::Screen has already had one interface for that. We
do the same for finding local window with ignored windows
as well.

Bug: 1069469
Change-Id: I59b4d3cb89a3bf4cf25beae82bc07cc468f4b50b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2157004
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Maksim Sisov <msisov@igalia.com>
Cr-Commit-Position: refs/heads/master@{#765115}

ash/display/screen_ash.cc

@@ -6,6 +6,7 @@
 
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/public/cpp/ash_switches.h"
+#include "ash/public/cpp/window_finder.h"
 #include "ash/root_window_controller.h"
 #include "ash/root_window_settings.h"
 #include "ash/shelf/shelf_widget.h"
@@ -47,7 +48,12 @@ class ScreenForShutdown : public display::Screen {
   gfx::Point GetCursorScreenPoint() override { return gfx::Point(); }
   bool IsWindowUnderCursor(gfx::NativeWindow window) override { return false; }
   gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) override {
-    return NULL;
+    return nullptr;
+  }
+  gfx::NativeWindow GetLocalProcessWindowAtPoint(
+      const gfx::Point& point,
+      const std::set<gfx::NativeWindow>& ignore) override {
+    return nullptr;
   }
   int GetNumDisplays() const override { return display_list_.size(); }
   const std::vector<display::Display>& GetAllDisplays() const override {
@@ -110,6 +116,12 @@ gfx::NativeWindow ScreenAsh::GetWindowAtScreenPoint(const gfx::Point& point) {
   return root_window->GetEventHandlerForPoint(local_point);
 }
 
+gfx::NativeWindow ScreenAsh::GetLocalProcessWindowAtPoint(
+    const gfx::Point& point,
+    const std::set<gfx::NativeWindow>& ignore) {
+  return ash::GetTopmostWindowAtPoint(point, ignore);
+}
+
 int ScreenAsh::GetNumDisplays() const {
   return GetDisplayManager()->GetNumDisplays();
 }

ash/display/screen_ash.h

@@ -33,6 +33,9 @@ class ASH_EXPORT ScreenAsh : public display::Screen {
   gfx::Point GetCursorScreenPoint() override;
   bool IsWindowUnderCursor(gfx::NativeWindow window) override;
   gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) override;
+  gfx::NativeWindow GetLocalProcessWindowAtPoint(
+      const gfx::Point& point,
+      const std::set<gfx::NativeWindow>& ignore) override;
   int GetNumDisplays() const override;
   const std::vector<display::Display>& GetAllDisplays() const override;
   display::Display GetDisplayNearestWindow(

chrome/browser/ui/BUILD.gn

@@ -2546,7 +2546,6 @@ jumbo_static_library("ui") {
       "views/frame/native_browser_frame_factory_mac.mm",
       "views/tab_contents/chrome_web_contents_view_delegate_views_mac.h",
       "views/tab_contents/chrome_web_contents_view_delegate_views_mac.mm",
-      "views/tabs/window_finder_mac.mm",
       "web_contents_sizer.mm",
       "webui/help/version_updater_mac.h",
       "webui/help/version_updater_mac.mm",
@@ -2618,7 +2617,6 @@ jumbo_static_library("ui") {
       "views/status_icons/status_tray_state_changer_win.h",
       "views/status_icons/status_tray_win.cc",
       "views/status_icons/status_tray_win.h",
-      "views/tabs/window_finder_win.cc",
       "views/try_chrome_dialog_win/arrow_border.cc",
       "views/try_chrome_dialog_win/arrow_border.h",
       "views/try_chrome_dialog_win/button_layout.cc",
@@ -2780,18 +2778,6 @@ jumbo_static_library("ui") {
     if (use_aura) {
       deps += [ "//third_party/fontconfig" ]
     }
-
-    # WindowFinder implementation selection is a bit tricky, so do all here
-    # to get it right and prevent ODR violations.
-    if (is_chromeos) {
-      sources += [ "views/tabs/window_finder_chromeos.cc" ]
-    } else if (use_x11) {
-      sources += [ "views/tabs/window_finder_x11.cc" ]
-      deps += [ "//ui/platform_window/x11" ]
-    } else {
-      assert(use_ozone)
-      sources += [ "views/tabs/window_finder_ozone.cc" ]
-    }
   }
 
   if (is_chromeos) {
@@ -3455,6 +3441,7 @@ jumbo_static_library("ui") {
       "views/tabs/tab_style_views.h",
       "views/tabs/tab_width_constraints.cc",
       "views/tabs/tab_width_constraints.h",
+      "views/tabs/window_finder.cc",
       "views/tabs/window_finder.h",
       "views/task_manager_view.cc",
       "views/task_manager_view.h",

chrome/browser/ui/views/tabs/window_finder_chromeos.cc → chrome/browser/ui/views/tabs/window_finder.cc

@@ -4,10 +4,11 @@
 
 #include "chrome/browser/ui/views/tabs/window_finder.h"
 
-#include "ash/public/cpp/window_finder.h"
+#include "ui/display/screen.h"
 
 gfx::NativeWindow WindowFinder::GetLocalProcessWindowAtPoint(
     const gfx::Point& screen_point,
     const std::set<gfx::NativeWindow>& ignore) {
-  return ash::GetTopmostWindowAtPoint(screen_point, ignore);
+  return display::Screen::GetScreen()->GetLocalProcessWindowAtPoint(
+      screen_point, ignore);
 }

chrome/browser/ui/views/tabs/window_finder.h

@@ -14,16 +14,18 @@ namespace gfx {
 class Point;
 }
 
-// Class used by the tabstrip to find chrome windows that we can attach tabs to.
+// Class used by the tabstrip to find chrome windows (through display::Screen)
+// that we can attach tabs to. We don't call
+// display::Screen::GetLocalProcessWindowAtPoint, but use this class just for
+// the sake of simplicity in unittests. That is, some of them want to set own
+// implementation of WindowFinder and emulate mouse movements. However, if they
+// set another screen, assertion that screen has been changed may be hit.
 class WindowFinder {
  public:
   WindowFinder() = default;
   virtual ~WindowFinder() = default;
 
-  // Finds the topmost visible chrome window at |screen_point|. This should
-  // return nullptr if |screen_point| is in another program's window which
-  // occludes the topmost chrome window. Ignores the windows in |ignore|, which
-  // contain windows such as the tab being dragged right now.
+  // See comment at display::Screen::GetLocalProcessWindowAtPoint().
   virtual gfx::NativeWindow GetLocalProcessWindowAtPoint(
       const gfx::Point& screen_point,
       const std::set<gfx::NativeWindow>& ignore);