Update to Chromium version 70.0.3538.0 (#587811)

Known issues:
- The CefLoadCRLSetsFile function needs to be re-implemented (see issue #2497).
- Linux: GTK2 support has been removed. The cefclient sample needs to be updated
  to use GTK3 (see issue #2014).

libcef/browser/extensions/extensions_browser_api_provider.h

@@ -0,0 +1,26 @@
+// Copyright 2018 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 CEF_LIBCEF_BROWSER_EXTENSIONS_EXTENSIONS_BROWSER_API_PROVIDER_H_
+#define CEF_LIBCEF_BROWSER_EXTENSIONS_EXTENSIONS_BROWSER_API_PROVIDER_H_
+
+#include "base/macros.h"
+#include "extensions/browser/extensions_browser_api_provider.h"
+
+namespace extensions {
+
+class CefExtensionsBrowserAPIProvider : public ExtensionsBrowserAPIProvider {
+ public:
+  CefExtensionsBrowserAPIProvider();
+  ~CefExtensionsBrowserAPIProvider() override;
+
+  void RegisterExtensionFunctions(ExtensionFunctionRegistry* registry) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CefExtensionsBrowserAPIProvider);
+};
+
+}  // namespace extensions
+
+#endif  // CEF_LIBCEF_BROWSER_EXTENSIONS_EXTENSIONS_BROWSER_API_PROVIDER_H_