Change queryId of launcherSearchProvider API to integer.

chrome/browser/chromeos/launcher_search_provider/service.cc

Index: chrome/browser/chromeos/launcher_search_provider/service.cc
diff --git a/chrome/browser/chromeos/launcher_search_provider/service.cc b/chrome/browser/chromeos/launcher_search_provider/service.cc
index 8ad4a6e47557176e5b9fd08b357bdcb9d2162154..84595955c923900dc6f18bd089da9f9eed6c6101 100644
--- a/chrome/browser/chromeos/launcher_search_provider/service.cc
+++ b/chrome/browser/chromeos/launcher_search_provider/service.cc
@@ -60,7 +60,7 @@ void Service::OnQueryStarted(app_list::LauncherSearchProvider* provider,
         make_scoped_ptr(new extensions::Event(
             api_launcher_search_provider::OnQueryStarted::kEventName,
             api_launcher_search_provider::OnQueryStarted::Create(
-                std::to_string(query_id_), query, max_result))));
+                query_id_, query, max_result))));
   }
 }
 
@@ -77,8 +77,7 @@ void Service::OnQueryEnded() {
         extension_id,
         make_scoped_ptr(new extensions::Event(
             api_launcher_search_provider::OnQueryEnded::kEventName,
-            api_launcher_search_provider::OnQueryEnded::Create(
-                std::to_string(query_id_)))));
+            api_launcher_search_provider::OnQueryEnded::Create(query_id_))));
   }
 
   is_query_running_ = false;
@@ -100,12 +99,12 @@ void Service::OnOpenResult(const ExtensionId& extension_id,
 void Service::SetSearchResults(
     const extensions::Extension* extension,
     scoped_ptr<ErrorReporter> error_reporter,
-    const std::string& query_id,
+    const int query_id,
     const std::vector<linked_ptr<
         extensions::api::launcher_search_provider::SearchResult>>& results) {
   // If query is not running or query_id is different from current query id,
   // discard the results.
-  if (!is_query_running_ || query_id != std::to_string(query_id_))
+  if (!is_query_running_ || query_id != query_id_)
     return;
 
   // If |extension| is not in the listener extensions list, ignore it.