Unbreak extension installation. Cleanup accidentally reversed
boolean logic. Difficult to test because this is way up close
to the UI.

Review URL: http://codereview.chromium.org/160002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21376 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/extensions_service.cc b/chrome/browser/extensions/extensions_service.cc
index 7d417bb..9dc74e4 100644
--- a/chrome/browser/extensions/extensions_service.cc
+++ b/chrome/browser/extensions/extensions_service.cc
@@ -1128,7 +1128,7 @@
 
   if (show_dialog) {
 #if defined(OS_WIN)
-    if (!win_util::MessageBox(GetForegroundWindow(),
+    if (win_util::MessageBox(GetForegroundWindow(),
             L"Are you sure you want to install this extension?\n\n"
             L"This is a temporary message and it will be removed when "
             L"extensions UI is finalized.",