chrome://plugins Mojo-ification part 1/2, adding interface.

chrome/browser/ui/webui/plugins/plugins.mojom

+// Copyright 2016 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.
+
+struct MimeType {
+  string description;
+  array<string> file_extensions;
+  string mime_type;
+};
+
+struct PluginFile {
+  string description;
+  string enabled_mode;
+  array<MimeType> mime_types;
+  string name;
+  string path;
+  string type;
+  string version;
+};
+
+struct PluginData {
+  bool always_allowed;
+  string description;
+  bool critical;
+  string enabled_mode;
+  string id;
+  string name;
+  string update_url;
+  string version;
+  array<PluginFile> plugin_files;
+};
+
+interface PluginsHandlerMojo {
+  GetPluginsData() => (array<PluginData> plugins);
+  GetShowDetails() => (bool show_details);
+  SaveShowDetailsToPrefs(bool details_mode);
+  SetPluginAlwaysAllowed(string plugin, bool allowed);
+  SetPluginEnabled(string plugin_path, bool enable);
+  SetPluginGroupEnabled(string group_name, bool enable);
+  SetClientPage(PluginsPageMojo page);
+};
+
+interface PluginsPageMojo {
+  OnPluginsUpdated(array<PluginData> plugins);
+};