Add a self-destruct mechanism to user-level Chrome Frame when it detects that system-level Chrome Frame is present. This is a first step to handling user-to-system-level handoff.

It will cause a user-level install to be correctly replaced with a system-level one once the user logs out and back in again. Additional changelists
will follow that:

1) Ensure full clean-up of the user-level installation.
2) Handle notifications such that logging out and in again isn't required.

BUG=82816
TEST=Install user-level Chrome Frame. 
Review URL: http://codereview.chromium.org/7065024

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@87033 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 17 insertions, 1 deletions

diff --git a/chrome_frame/chrome_frame_helper_util.h b/chrome_frame/chrome_frame_helper_util.h
index d80b07d..28a1f88 100644
--- a/chrome_frame/chrome_frame_helper_util.h
+++ b/chrome_frame/chrome_frame_helper_util.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -68,4 +68,20 @@ HWND RecurseFindWindow(HWND parent,
                        DWORD thread_id_to_match,
                        DWORD process_id_to_match);
 
+// Reads |value_size| characters from a value named |value_name| in |key| and
+// places them in the buffer pointed to by |value|. Returns ERROR_SUCCESS on
+// success.
+LONG ReadValue(HKEY key,
+               const wchar_t* value_name,
+               size_t value_size,
+               wchar_t* value);
+
+
+// Returns true if our BHO is registered in the HKLM subkey that IE checks for
+// the list of BHOs to load.
+bool IsBHOLoadingPolicyRegistered();
+
+// Returns true if system-level Chrome Frame is installed.
+bool IsSystemLevelChromeFrameInstalled();
+
 #endif  // CHROME_FRAME_CHROME_FRAME_HELPER_UTIL_H_