aw: Remove global AllowWait on UI thread

android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h

Index: android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h
diff --git a/android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h b/android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h
deleted file mode 100644
index af2154b6437b6a976972604953818c8e9717425c..0000000000000000000000000000000000000000
--- a/android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef ANDROID_WEBVIEW_BROWSER_SCOPED_ALLOW_WAIT_FOR_LEGACY_WEB_VIEW_API_H
-#define ANDROID_WEBVIEW_BROWSER_SCOPED_ALLOW_WAIT_FOR_LEGACY_WEB_VIEW_API_H
-
-#include "base/threading/thread_restrictions.h"
-
-// This class is only available when building the chromium back-end for android
-// webview: it is required where API backward compatibility demands that the UI
-// thread must block waiting on other threads e.g. to obtain a synchronous
-// return value. Long term, asynchronous overloads of all such methods will be
-// added in the public API, and and no new uses of this will be allowed.
-class ScopedAllowWaitForLegacyWebViewApi {
- private:
-  base::ThreadRestrictions::ScopedAllowWait wait;
-};
-
-#endif  // ANDROID_WEBVIEW_BROWSER_SCOPED_ALLOW_WAIT_FOR_LEGACY_WEB_VIEW_API_H