Don't register or use the DelegateExecute verb handler if it isn't present.

chrome/installer/setup/uninstall.cc

 // Copyright (c) 2012 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.
 //
 // This file defines the methods useful for uninstalling Chrome.
 
 #include "chrome/installer/setup/uninstall.h"
 
 #include <vector>
 
@@ skipping 683 matching lines @@
     ext_association.append(L"\\");
     ext_association.append(chrome::kExtensionFileExtension);
     InstallUtil::DeleteRegistryKey(roots[i], ext_association);
   }
 }
 
 // Builds and executes a work item list to remove DelegateExecute verb handler
 // work items for |product|.  This will be a noop for products whose
 // corresponding BrowserDistribution implementations do not publish
 // DelegateExecute data via an implementation of GetDelegateExecuteHandlerData.
-bool ProcessDelegateExecuteWorkItems(const InstallationState& original_state,
-                                     const InstallerState& installer_state,
+bool ProcessDelegateExecuteWorkItems(const InstallerState& installer_state,
                                      const FilePath& setup_path,

[gab, 2012/04/25 05:18:29]

|setup_path| is now unused.

[grt (UTC plus 2), 2012/04/25 13:05:11]

Good catch.  Done.

                                      const Product& product) {
   scoped_ptr<WorkItemList> item_list(WorkItem::CreateNoRollbackWorkItemList());
-  AddDelegateExecuteWorkItems(original_state, installer_state, setup_path,
-                              Version(), product, item_list.get());
+  AddDelegateExecuteWorkItems(installer_state, FilePath(), Version(), product,

[gab, 2012/04/25 05:18:29]

I don't like having to create empty FilePath and Version objects here, but I
realize there is no such thing as passing a null reference in C++. What about
making the interface use pointers instead of references? I guess that puts the
burden in AddDelegateExecuteWorkItems now having to check for null-ptrs..?

Just looking for C++ coding insights :)

[grt (UTC plus 2), 2012/04/25 13:05:11]

For the most part, pointers are used for out/inout params in Chromium.  Although
the style guide permits const Foo*, it discourages its use.  I think it
generally reduces readability to do so since it's so rare.

An alternative would be to create an AddRemoveDelegateExecuteWorkItems function,
or somesuch, that only takes the params required to remove the registration. 
I'm hesitant to do this, though, since the remove code is hit during installs
and because it separates the implementation of the two.  Also, there's precedent
in the installer for funcs to do double-duty like this.

+                              item_list.get());
   return item_list->Do();
 }
 
 bool ProcessChromeFrameWorkItems(const InstallationState& original_state,
                                  const InstallerState& installer_state,
                                  const FilePath& setup_path,
                                  const Product& product) {
   if (!product.is_chrome_frame())
     return false;
 
@@ skipping 102 matching lines @@
   // self-destruct following the installation of system-level Chrome (because
   // the system-level Chrome owns the HKLM registration now), and 2) this user
   // had made Chrome their default browser.
   if (installer_state.system_install() ||
       (remove_all &&
        (!suffix.empty() || CurrentUserHasDefaultBrowser(installer_state)))) {
     DeleteChromeRegistrationKeys(product.distribution(), HKEY_LOCAL_MACHINE,
                                  suffix, installer_state.target_path(), &ret);
   }
 
-  ProcessDelegateExecuteWorkItems(original_state, installer_state, setup_path,
-                                  product);
+  ProcessDelegateExecuteWorkItems(installer_state, setup_path, product);
 
   if (!is_chrome) {
     ProcessChromeFrameWorkItems(original_state, installer_state, setup_path,
                                 product);
   }
 
   if (installer_state.is_multi_install())
     ProcessGoogleUpdateItems(original_state, installer_state, product);
 
   ProcessQuickEnableWorkItems(installer_state, original_state);
@@ skipping 110 matching lines @@
 
   // Try and delete the preserved local state once the post-install
   // operations are complete.
   if (!backup_state_file.empty())
     file_util::Delete(backup_state_file, false);
 
   return ret;
 }
 
 }  // namespace installer