Dismiss the dropdown combobox when clicking outside of it.

There was a code that does it. However, it regressed at some point.
In https://chromium-review.googlesource.com/c/chromium/src/+/1638126/4/ui/views/controls/editable_combobox/editable_combobox.cc#273
it was suggested to compare event->flags() == event->changed_button_flags(). It
doesn't work anymore because changed_button_flags is EF_LEFT_MOUSE_BUTTON and
flags is EF_LEFT_MOUSE_BUTTON | EF_NUM_LOCK_ON.

Bug: 1016289
Change-Id: I463cdc5007161cf6a909c41bf8a96fd01ac841f5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1872578Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708574}

ui/views/controls/editable_combobox/editable_combobox.cc

@@ -277,7 +277,7 @@ class EditableCombobox::EditableComboboxPreTargetHandler
   // ui::EventHandler overrides.
   void OnMouseEvent(ui::MouseEvent* event) override {
     if (event->type() == ui::ET_MOUSE_PRESSED &&
-        event->flags() == event->changed_button_flags())
+        event->button_flags() == event->changed_button_flags())
       HandlePressEvent(event->root_location());
   }
 

ui/views/controls/editable_combobox/editable_combobox_unittest.cc

@@ -249,9 +249,9 @@ bool EditableComboboxTest::IsMenuOpen() {
 void EditableComboboxTest::PerformMouseEvent(Widget* widget,
                                              const gfx::Point& point,
                                              const ui::EventType type) {
-  ui::MouseEvent event =
-      ui::MouseEvent(type, point, point, ui::EventTimeForNow(),
-                     ui::EF_LEFT_MOUSE_BUTTON, ui::EF_LEFT_MOUSE_BUTTON);
+  ui::MouseEvent event = ui::MouseEvent(
+      type, point, point, ui::EventTimeForNow(),
+      ui::EF_LEFT_MOUSE_BUTTON | ui::EF_NUM_LOCK_ON, ui::EF_LEFT_MOUSE_BUTTON);
   widget->OnMouseEvent(&event);
 }