Moves FindDisplayIndexContainingPoint into display

ui/display/manager/display_manager.cc

Index: ui/display/manager/display_manager.cc
diff --git a/ui/display/manager/display_manager.cc b/ui/display/manager/display_manager.cc
index 68b7abf0427134e5ce1e66c160347380af3767cd..36d8ac8afd58910254d54c84a31944e5b879b9f5 100644
--- a/ui/display/manager/display_manager.cc
+++ b/ui/display/manager/display_manager.cc
@@ -27,6 +27,7 @@
 #include "base/threading/thread_task_runner_handle.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/display/display.h"
+#include "ui/display/display_finder.h"
 #include "ui/display/display_observer.h"
 #include "ui/display/display_switches.h"
 #include "ui/display/manager/display_layout_store.h"
@@ -271,9 +272,9 @@ const Display& DisplayManager::GetDisplayForId(int64_t id) const {
 
 const Display& DisplayManager::FindDisplayContainingPoint(
     const gfx::Point& point_in_screen) const {
-  int index =
-      FindDisplayIndexContainingPoint(active_display_list_, point_in_screen);
-  return index < 0 ? GetInvalidDisplay() : active_display_list_[index];
+  auto iter = display::FindDisplayContainingPoint(active_display_list_,
+                                                  point_in_screen);
+  return iter == active_display_list_.end() ? GetInvalidDisplay() : *iter;
 }
 
 bool DisplayManager::UpdateWorkAreaOfDisplay(int64_t display_id,