app_list: Refactor mixer groups to avoid hard-coded groups in Mixer.

ui/app_list/search/mixer_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <set>
 #include <string>
 
 #include "base/memory/scoped_vector.h"
 #include "base/strings/string16.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/app_list/app_list_model.h"
 #include "ui/app_list/search/history_types.h"
 #include "ui/app_list/search/mixer.h"
 #include "ui/app_list/search_provider.h"
 #include "ui/app_list/search_result.h"
 
 namespace app_list {
 namespace test {
 
+// Maximum number of results to show in each mixer group.
+const size_t kMaxAppsGroupResults = 4;
+const size_t kMaxOmniboxResults = 0;  // Unlimited.
+const size_t kMaxWebstoreResults = 2;
+const size_t kMaxPeopleResults = 2;
+
 class TestSearchResult : public SearchResult {
  public:
   TestSearchResult(const std::string& id, double relevance)
       : instance_id_(instantiation_count++) {
     set_id(id);
     set_title(base::UTF8ToUTF16(id));
     set_relevance(relevance);
   }
   ~TestSearchResult() override {}
 
@@ skipping 72 matching lines @@
     results_.reset(new AppListModel::SearchResults);
 
     providers_.push_back(new TestSearchProvider("app"));
     providers_.push_back(new TestSearchProvider("omnibox"));
     providers_.push_back(new TestSearchProvider("webstore"));
     providers_.push_back(new TestSearchProvider("people"));
 
     is_voice_query_ = false;
 
     mixer_.reset(new Mixer(results_.get()));
-    mixer_->Init();
-    mixer_->AddProviderToGroup(Mixer::MAIN_GROUP, providers_[0]);
-    mixer_->AddProviderToGroup(Mixer::OMNIBOX_GROUP, providers_[1]);
-    mixer_->AddProviderToGroup(Mixer::WEBSTORE_GROUP, providers_[2]);
-    mixer_->AddProviderToGroup(Mixer::PEOPLE_GROUP, providers_[3]);
+
+    size_t apps_group_id = mixer_->AddGroup(kMaxAppsGroupResults, 3.0);
+    size_t omnibox_group_id = mixer_->AddOmniboxGroup(kMaxOmniboxResults, 2.0);
+    size_t webstore_group_id = mixer_->AddGroup(kMaxWebstoreResults, 1.0);
+    size_t people_group_id = mixer_->AddGroup(kMaxPeopleResults, 0.0);
+
+    mixer_->AddProviderToGroup(apps_group_id, providers_[0]);
+    mixer_->AddProviderToGroup(omnibox_group_id, providers_[1]);
+    mixer_->AddProviderToGroup(webstore_group_id, providers_[2]);
+    mixer_->AddProviderToGroup(people_group_id, providers_[3]);
   }
 
   void RunQuery() {
     const base::string16 query;
 
     for (size_t i = 0; i < providers_.size(); ++i) {
       providers_[i]->Start(is_voice_query_, query);
       providers_[i]->Stop();
     }
 
@@ skipping 243 matching lines @@
   EXPECT_EQ(old_ui_result_ids[0],
             TestSearchResult::GetInstanceId(ui_results.GetItemAt(3)));
   EXPECT_EQ(old_ui_result_ids[1],
             TestSearchResult::GetInstanceId(ui_results.GetItemAt(0)));
   EXPECT_EQ(old_ui_result_ids[2],
             TestSearchResult::GetInstanceId(ui_results.GetItemAt(2)));
 }
 
 }  // namespace test
 }  // namespace app_list