Don't try to delete file type ownership at uninstall.

chrome/installer/setup/uninstall.cc

 // 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.
 //
 // This file defines the methods useful for uninstalling Chrome.
 
 #include "chrome/installer/setup/uninstall.h"
 
 #include "base/file_util.h"
 #include "base/path_service.h"
@@ skipping 605 matching lines @@
            &ShellUtil::kPotentialProtocolAssociations[0];
        *proto != NULL;
        ++proto) {
     parent_key.resize(base_length);
     file_util::AppendToPath(&parent_key, *proto);
     child_key.assign(parent_key).append(ShellUtil::kRegShellOpen);
     InstallUtil::DeleteRegistryKeyIf(root, parent_key, child_key, L"",
                                      open_command_pred);
   }
 
-  // Delete each filetype association if it references this Chrome.
-  InstallUtil::ValueEquals prog_id_pred(ShellUtil::kChromeHTMLProgId +
-                                        browser_entry_suffix);
-  for (const wchar_t* const* filetype = &ShellUtil::kFileAssociations[0];
-       *filetype != NULL; ++filetype) {
-    parent_key.resize(base_length);
-    file_util::AppendToPath(&parent_key, *filetype);
-    InstallUtil::DeleteRegistryKeyIf(root, parent_key, parent_key, L"",
-                                     prog_id_pred);
-  }
+  // Note that we do not attempt to delete filetype associations since MSDN
+  // says "Windows respects the Default value only if the ProgID found there is
+  // a registered ProgID. If the ProgID is unregistered, it is ignored."
 
   *exit_code = installer::UNINSTALL_SUCCESSFUL;
   return true;
 }
 
 void RemoveChromeLegacyRegistryKeys(BrowserDistribution* dist) {
   // We used to register Chrome to handle crx files, but this turned out
   // to be not worth the hassle. Remove these old registry entries if
   // they exist. See: http://codereview.chromium.org/210007
 
@@ skipping 254 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