Add quotes around executable pathes in the mini installer

chrome/installer/mini_installer/mini_installer.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.
 
 // mini_installer.exe is the first exe that is run when chrome is being
 // installed or upgraded. It is designed to be extremely small (~5KB with no
 // extra resources linked) and it has two main jobs:
 //   1) unpack the resources (possibly decompressing some)
 //   2) run the real installer (setup.exe) with appropriate flags.
 //
@@ skipping 211 matching lines @@
 }
 
 // Gets the setup.exe path from Registry by looking the value of Uninstall
 // string.  |size| is measured in wchar_t units.
 bool GetSetupExePathForGuidFromRegistry(bool system_level,
                                         const wchar_t* app_guid,
                                         wchar_t* path,
                                         size_t size) {
   const HKEY root_key = system_level ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
   RegKey key;
-  return OpenClientStateKey(root_key, app_guid, KEY_QUERY_VALUE, &key) &&
-      (key.ReadValue(kUninstallRegistryValueName, path, size) == ERROR_SUCCESS);
+  wchar_t unquoted_path[MAX_PATH] = {0};
+  if (!OpenClientStateKey(root_key, app_guid, KEY_QUERY_VALUE, &key) ||
+      (key.ReadValue(kUninstallRegistryValueName,
+                     unquoted_path,

[tommi (sloooow) - chröme, 2014/02/04 21:55:14]

I mean here.  Since unquoted_path will contain a value read from the registry,
how can you know that it is guaranteed to be unquoted?  I don't see any checks
for it.

What I'm being paranoid about is if there are any changes made to the code that
sets this value and someone "fixes" the quote problem on that side, not
realizing the effect it might have on this code.
Would it make sense to copy unquoted_path directly over to path if
unquoted_path[0] == '\"'?

[Cris Neckar, 2014/02/04 22:53:05]

Ah I misunderstood, thought you were asking if this code saves the path
somewhere after quoting it. 

Done.

+                     MAX_PATH) != ERROR_SUCCESS)) {
+    return false;
+  }
+
+  return !SafeStrCopy(path, size, L"\"") &&
+         !SafeStrCat(path, size, unquoted_path) &&
+         !SafeStrCat(path, size, L"\"");
 }
 
 // Gets the setup.exe path from Registry by looking the value of Uninstall
 // string.  |size| is measured in wchar_t units.
 bool GetSetupExePathFromRegistry(const Configuration& configuration,
                                  wchar_t* path,
                                  size_t size) {
   bool system_level = configuration.is_system_level();
 
   // If this is a multi install, first try looking in the binaries for the path.
@@ skipping 609 matching lines @@
     case 1:
       dest8[count - 1] = c;
   }
 
   while (adjcount-- > 0)  // Copy the rest, 4 bytes/32 bits at a time
     *(dest32++) = fill;
 
   return dest;
 }
 }  // extern "C"