Allow AppSearchProvider to provide recommendations.

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

Index: chrome/browser/ui/app_list/search/app_search_provider.cc
diff --git a/chrome/browser/ui/app_list/search/app_search_provider.cc b/chrome/browser/ui/app_list/search/app_search_provider.cc
index 9237b076500c9b6c34b8061ede32b14b23132dd5..ce3e8c93375e76fee59ffaa9310eee8f58bd9793 100644
--- a/chrome/browser/ui/app_list/search/app_search_provider.cc
+++ b/chrome/browser/ui/app_list/search/app_search_provider.cc
@@ -14,6 +14,7 @@
 #include "chrome/browser/ui/app_list/search/app_result.h"
 #include "chrome/browser/ui/app_list/search/tokenized_string.h"
 #include "chrome/browser/ui/app_list/search/tokenized_string_match.h"
+#include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
@@ -25,18 +26,25 @@ namespace app_list {
 
 class AppSearchProvider::App {
  public:
-  explicit App(const extensions::Extension* extension)
+  explicit App(const extensions::Extension* extension,
+               const base::Time& last_launch_time)
       : app_id_(extension->id()),
-        indexed_name_(base::UTF8ToUTF16(extension->name())) {
-  }
+        indexed_name_(base::UTF8ToUTF16(extension->name())),
+        last_launch_time_(last_launch_time) {}

[Matt Giuca, 2014/07/23 01:53:18]

nit: Is this ClangFormatted? I believe you should have a newline in between the
braces (but trust git cl format over me).

[calamity, 2014/07/28 02:55:26]

Yeah, git cl format wants this apparently.

[Matt Giuca, 2014/07/28 02:59:35]

Acknowledged.

   ~App() {}
 
   const std::string& app_id() const { return app_id_; }
   const TokenizedString& indexed_name() const { return indexed_name_; }
+  const base::Time& last_launch_time() const { return last_launch_time_; }
+
+  static bool AppLaunchedMoreRecent(App* const app1, App* const app2) {

[Matt Giuca, 2014/07/23 01:53:18]

"App* const"? Did you mean "const App*"?

("App* const" means an unmodifiable pointer to a non-constant App -- essentially
the same as writing "const int x", and not really helpful, unless std::sort
requires it, which I doubt.)

[calamity, 2014/07/28 02:55:27]

Removed.

+    return app1->last_launch_time() > app2->last_launch_time();
+  }
 
  private:
   const std::string app_id_;
   TokenizedString indexed_name_;
+  base::Time last_launch_time_;
 
   DISALLOW_COPY_AND_ASSIGN(App);
 };
@@ -53,27 +61,45 @@ AppSearchProvider::AppSearchProvider(Profile* profile,
 AppSearchProvider::~AppSearchProvider() {}
 
 void AppSearchProvider::Start(const base::string16& query) {
+  StartImpl(base::Time::Now(), query);
+}
+
+void AppSearchProvider::Stop() {
+}
+
+void AppSearchProvider::StartImpl(const base::Time& current_time,
+                                  const base::string16& query) {
   const TokenizedString query_terms(query);
 
   ClearResults();
 
-  TokenizedStringMatch match;
+  bool show_recommendations = query.empty();
+  // Refresh list of apps to ensure we have the latest launch time information.
+  if (show_recommendations)
+    RefreshApps();
+
   for (Apps::const_iterator app_it = apps_.begin();
        app_it != apps_.end();
        ++app_it) {
-    if (!match.Calculate(query_terms, (*app_it)->indexed_name()))
-      continue;
-
     scoped_ptr<AppResult> result(
         new AppResult(profile_, (*app_it)->app_id(), list_controller_));
-    result->UpdateFromMatch((*app_it)->indexed_name(), match);
+    if (show_recommendations) {
+      result->set_title((*app_it)->indexed_name().text());
+      result->UpdateFromLastLaunched(current_time,
+                                     (*app_it)->last_launch_time());
+    } else {
+      TokenizedStringMatch match;
+      if (!match.Calculate(query_terms, (*app_it)->indexed_name()))
+        continue;
+
+      result->UpdateFromMatch((*app_it)->indexed_name(), match);
+    }
     Add(result.PassAs<SearchResult>());
   }
 }
 
-void AppSearchProvider::Stop() {}
-
 void AppSearchProvider::AddApps(const extensions::ExtensionSet& extensions) {
+  extensions::ExtensionPrefs* prefs = extensions::ExtensionPrefs::Get(profile_);
   for (extensions::ExtensionSet::const_iterator iter = extensions.begin();
        iter != extensions.end(); ++iter) {
     const extensions::Extension* app = iter->get();
@@ -84,7 +110,8 @@ void AppSearchProvider::AddApps(const extensions::ExtensionSet& extensions) {
     if (profile_->IsOffTheRecord() &&
         !extensions::util::CanLoadInIncognito(app, profile_))
       continue;
-    apps_.push_back(new App(app));
+
+    apps_.push_back(new App(app, prefs->GetLastLaunchTime(app->id())));
   }
 }
 
@@ -94,6 +121,7 @@ void AppSearchProvider::RefreshApps() {
   AddApps(registry->enabled_extensions());
   AddApps(registry->disabled_extensions());
   AddApps(registry->terminated_extensions());
+  std::sort(apps_.begin(), apps_.end(), &App::AppLaunchedMoreRecent);

[Matt Giuca, 2014/07/23 01:53:18]

Question: Does this actually need to be sorted here? I thought the search
provider system would automatically order results by their "relevance" score
(which is indirectly based on the apps' last launch time). So why do you also
need to directly sort on last launch time?

[calamity, 2014/07/28 02:55:27]

You are indeed correct. This should have been removed. Made it so.

 }
 
 void AppSearchProvider::OnExtensionLoaded(