Use whether a query is from the app list to determine the RLZ parameter.

chrome/browser/ui/app_list/search/omnibox_provider.cc

Index: chrome/browser/ui/app_list/search/omnibox_provider.cc
diff --git a/chrome/browser/ui/app_list/search/omnibox_provider.cc b/chrome/browser/ui/app_list/search/omnibox_provider.cc
index 4ca991c6aa0d4307578304576eff203db102a41a..97c65517e5658b480585d8836d475a9041dbf705 100644
--- a/chrome/browser/ui/app_list/search/omnibox_provider.cc
+++ b/chrome/browser/ui/app_list/search/omnibox_provider.cc
@@ -136,6 +136,7 @@ OmniboxProvider::OmniboxProvider(Profile* profile)
           profile,
           this,
           AutocompleteClassifier::kDefaultOmniboxProviders)) {

[Peter Kasting, 2014/04/09 02:12:33]

You should consider using a different provider set here.  You don't need
ZeroSuggest, and I would imagine there are probably other providers you don't
actually want either (though I'm not totally sure).

Depending on how different your set ends up being from the default set you could
either construct the appropriate value from scratch or just mask the default
value a bit.

[Sam McNally, 2014/04/09 05:33:44]

Done. Other than zero suggest, the rest of the defaults seem reasonable to me.

+xiyuan FYI.

+  controller_->search_provider()->set_in_app_list();
 }
 
 OmniboxProvider::~OmniboxProvider() {}