Implement a modal permission dialog on Android gated by a feature.

chrome/browser/android/chrome_jni_registrar.cc

Index: chrome/browser/android/chrome_jni_registrar.cc
diff --git a/chrome/browser/android/chrome_jni_registrar.cc b/chrome/browser/android/chrome_jni_registrar.cc
index bc25123c3a5a07c6c28ab29813d3a02b7dec0178..7abb0b20ddffe108daf97fae955eed70e8f03c6e 100644
--- a/chrome/browser/android/chrome_jni_registrar.cc
+++ b/chrome/browser/android/chrome_jni_registrar.cc
@@ -119,6 +119,7 @@
 #include "chrome/browser/notifications/notification_platform_bridge_android.h"
 #include "chrome/browser/password_manager/account_chooser_dialog_android.h"
 #include "chrome/browser/password_manager/auto_signin_first_run_dialog_android.h"
+#include "chrome/browser/permissions/permission_dialog_delegate.h"
 #include "chrome/browser/permissions/permission_update_infobar_delegate_android.h"
 #include "chrome/browser/predictors/resource_prefetch_predictor_android.h"
 #include "chrome/browser/prerender/external_prerender_handler_android.h"
@@ -331,6 +332,8 @@ static base::android::RegistrationMethod kChromeRegisteredMethods[] = {
      autofill::PasswordGenerationPopupViewAndroid::Register},
     {"PasswordUIViewAndroid",
      PasswordUIViewAndroid::RegisterPasswordUIViewAndroid},
+    {"PermissionDialogDelegate",
+     PermissionDialogDelegate::RegisterPermissionDialogDelegate},
     {"PermissionUpdateInfoBarDelegate",
      PermissionUpdateInfoBarDelegate::RegisterPermissionUpdateInfoBarDelegate},
     {"PersonalDataManagerAndroid",