Ensure permission bubble is stacked below the exclusive access bubble.

chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm

Index: chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm
diff --git a/chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm b/chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm
index 7fd122adff59a88b8c1511de98b161e1daa5a236..79dd2e84ec37f6010ea7751986621f25b7e87a13 100644
--- a/chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm
+++ b/chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.mm
@@ -17,6 +17,7 @@
 #include "components/prefs/pref_service.h"
 #include "ui/base/cocoa/cocoa_base_utils.h"
 #import "ui/gfx/mac/coordinate_conversion.h"
+#include "ui/views/widget/widget.h"
 
 ExclusiveAccessController::ExclusiveAccessController(
     BrowserWindowController* controller,
@@ -86,6 +87,13 @@ void ExclusiveAccessController::Layout(CGFloat max_y) {
     views_bubble_->RepositionIfVisible();
 }
 
+gfx::NativeView ExclusiveAccessController::GetNativeView() {
+  if (!views_bubble_)
+    return nullptr;
+
+  return views_bubble_->GetWidget()->GetNativeView();
+}
+
 Profile* ExclusiveAccessController::GetProfile() {
   return browser_->profile();
 }