Rearrange a few settings into System category page.

- Use activity-alias to define which activity shows up in what category.
  We choose activity-alias because it creates a reference to UI we need
  without having to define a new set of intent-filter and/or category
  keys. This reduces maintainence in the long run. We should merge
  metadata from activity-alias into targetActivity when cleaning up.

- Created new System dashboard activity that hosts all system category
  tiles dynamically, and a static tile for checking system update.

Bug: 31781480
Test: manual
Test: make RunSettingsRoboTests -j40
Change-Id: Ia2d762e3e1aebd17423a395c5e6c286dc3326492

src/com/android/settings/dashboard/DashboardFeatureProvider.java

@@ -16,6 +16,7 @@
 package com.android.settings.dashboard;
 
 import com.android.settingslib.drawer.DashboardCategory;
+import com.android.settingslib.drawer.Tile;
 
 import java.util.List;
 
@@ -34,8 +35,20 @@ public interface DashboardFeatureProvider {
      */
     DashboardCategory getTilesForHomepage();
 
+    /**
+     * Get tiles (wrapped in {@link DashboardCategory}) for system category.
+     */
+    DashboardCategory getTilesForSystemCategory();
+
     /**
      * Get all tiles, grouped by category.
      */
     List<DashboardCategory> getAllCategories();
+
+    /**
+     * Returns a priority group for tile. priority level is grouped into hundreds. tiles with
+     * priority 100 - 199 belongs to priority level 100, tiles with priority 200 - 299 is in
+     * group 200, and so on.
+     */
+    int getPriorityGroup(Tile tile);
 }

src/com/android/settings/dashboard/DashboardFeatureProviderImpl.java

@@ -21,6 +21,7 @@ import android.content.Context;
 import com.android.settingslib.drawer.CategoryKey;
 import com.android.settingslib.drawer.CategoryManager;
 import com.android.settingslib.drawer.DashboardCategory;
+import com.android.settingslib.drawer.Tile;
 
 import java.util.List;
 
@@ -48,8 +49,18 @@ public class DashboardFeatureProviderImpl implements DashboardFeatureProvider {
         return mCategoryManager.getTilesByCategory(mContext, CategoryKey.CATEGORY_HOMEPAGE);
     }
 
+    @Override
+    public DashboardCategory getTilesForSystemCategory() {
+        return mCategoryManager.getTilesByCategory(mContext, CategoryKey.CATEGORY_SYSTEM);
+    }
+
     @Override
     public List<DashboardCategory> getAllCategories() {
         return mCategoryManager.getCategories(mContext);
     }
+
+    @Override
+    public int getPriorityGroup(Tile tile) {
+        return tile.priority / 100;
+    }
 }

src/com/android/settings/dashboard/DashboardTilePreference.java

@@ -0,0 +1,45 @@
+/**
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.settings.dashboard;
+
+import android.content.Context;
+import android.util.AttributeSet;
+
+import com.android.settings.DividerPreference;
+import com.android.settings.R;
+
+/**
+ * A {@code Preference} styled as a dashboard tile.
+ */
+public class DashboardTilePreference extends DividerPreference {
+
+    public DashboardTilePreference(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init();
+    }
+
+    public DashboardTilePreference(Context context) {
+        super(context);
+        init();
+    }
+
+    private void init() {
+        setLayoutResource(R.layout.dashboard_tile);
+        setDividerAllowedAbove(false);
+        setDividerAllowedBelow(false);
+    }
+
+}