First pass at experimental omnibox API. There are plenty of rough edges and

chrome/browser/extensions/extension_omnibox_api.h

+// Copyright (c) 2010 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 CHROME_BROWSER_EXTENSIONS_EXTENSION_OMNIBOX_API_H_
+#define CHROME_BROWSER_EXTENSIONS_EXTENSION_OMNIBOX_API_H_
+
+#include "chrome/browser/extensions/extension_function.h"
+
+class ListValue;
+
+// Event router class for events related to the omnibox API.
+class ExtensionOmniboxEventRouter {
+ public:
+  // The user has changed what is typed into the omnibox while in an extension
+  // keyword session. Returns true if someone is listening to this event, and
+  // thus we have some degree of confidence we'll get a response.
+  static bool OnInputChanged(
+      Profile* profile, const std::string& extension_id,
+      const std::string& input, int suggest_id);
+
+  // The user has accepted the omnibox input.
+  static void OnInputEntered(
+      Profile* profile, const std::string& extension_id,
+      const std::string& input);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ExtensionOmniboxEventRouter);
+};
+
+class OmniboxSendSuggestionsFunction : public SyncExtensionFunction {
+ public:
+  virtual bool RunImpl();
+  DECLARE_EXTENSION_FUNCTION_NAME("experimental.omnibox.sendSuggestions");
+};
+
+typedef std::pair<int, ListValue*> ExtensionOmniboxSuggestions;
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_OMNIBOX_API_H_