Enable MSVC warning for unused locals.

chrome/browser/search/suggestions/suggestions_source.cc

Index: chrome/browser/search/suggestions/suggestions_source.cc
diff --git a/chrome/browser/search/suggestions/suggestions_source.cc b/chrome/browser/search/suggestions/suggestions_source.cc
index a79589ad2995e64dfd7b5a9a29867cfbd967ebf2..e00b5126e4a4fb7e966dbbe9b06feb439979f51f 100644
--- a/chrome/browser/search/suggestions/suggestions_source.cc
+++ b/chrome/browser/search/suggestions/suggestions_source.cc
@@ -116,11 +116,8 @@ std::string SuggestionsSource::GetSource() const {
 void SuggestionsSource::StartDataRequest(
     const std::string& path, int render_process_id, int render_frame_id,
     const content::URLDataSource::GotDataCallback& callback) {
-  SuggestionsServiceFactory* suggestions_service_factory =

[sky, 2014/11/18 03:33:31]

Does MSVC really complain about this style?

[Peter Kasting, 2014/11/18 06:23:17]

Yes :(

I think this is some kind of bug.  I can't figure out what conditions trigger
it, since it complains rarely.

[jamesr, 2014/11/18 06:30:58]

Have you filed a bug?  Transforms like this make the code less readable, imo,
especially if the expression is long enough to induce line wrapping where it
wouldn't exist otherwise.

[Peter Kasting, 2014/11/18 06:36:06]

I have not filed a bug, in part because, as I said, I can't figure out what
conditions trigger this, and in part because it affected a very small number of
cases across the entire codebase, and the transforms in question generally
improved readability rather than hindering it IMO (here, for example), so I
haven't had a lot of motivation to spend time trying to narrow things down.

-      SuggestionsServiceFactory::GetInstance();
-
   SuggestionsService* suggestions_service(
-      suggestions_service_factory->GetForProfile(profile_));
+      SuggestionsServiceFactory::GetInstance()->GetForProfile(profile_));
 
   if (!suggestions_service) {
     callback.Run(NULL);