Delete the NPAPI plugin browsertests.

content/test/plugin/plugin_windowless_test.h

-// Copyright (c) 2011 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 CONTENT_TEST_PLUGIN_PLUGIN_WINDOWLESS_TEST_H_
-#define CONTENT_TEST_PLUGIN_PLUGIN_WINDOWLESS_TEST_H_
-
-#include "base/compiler_specific.h"
-#include "content/test/plugin/plugin_test.h"
-
-namespace NPAPIClient {
-
-// This class contains a list of windowless plugin tests. Please add additional
-// tests to this class.
-class WindowlessPluginTest : public PluginTest {
- public:
-  // Constructor.
-  WindowlessPluginTest(NPP id, NPNetscapeFuncs *host_functions);
-
-  // These tests run in windowless plugin mode.
-  bool IsWindowless() const override;
-
-  // NPAPI HandleEvent handler
-  NPError New(uint16 mode,
-              int16 argc,
-              const char* argn[],
-              const char* argv[],
-              NPSavedData* saved) override;
-  int16 HandleEvent(void* event) override;
-
- protected:
-  NPError ExecuteScript(NPNetscapeFuncs* browser, NPP id,
-      const std::string& script, NPVariant* result);
-  void ExecuteScriptDeleteInPaint(NPNetscapeFuncs* browser);
-  void ExecuteScriptResizeInPaint(NPNetscapeFuncs* browser);
-  void MultipleInstanceSyncCalls(NPNetscapeFuncs* browser);
-  void ConvertPoint(NPNetscapeFuncs* browser);
-
-  int paint_counter_;
-};
-
-}  // namespace NPAPIClient
-
-#endif  // CONTENT_TEST_PLUGIN_PLUGIN_WINDOWLESS_TEST_H_