Storage Settings hides categories when loading

To hide sorting animation.

- Storage Settings always loads cache and updates UI, then
  loads storage size and updates UI.
  Remove the chche design because storage category preferences
  will hide during loading, it no meaning to load from cache
  and update UI.

- Hides loading circle before storage category preferences
  become visible, it prevents flickers.

- Remove Calculating... summary of StorageItemPreference.

- Private storage category preferences and secondary user
  preference become visible at
  StorageItemPreferenceController#onLoadFinished.

Bug: 188731179
Bug: 185547228
Bug: 188615591
Test: atest com.android.settings.deviceinfo
      atest com.android.settings.deviceinfo.storage
      make RunSettingsRoboTests -j ROBOTEST_FILTER=com.android.settings.deviceinfo
      make RunSettingsRoboTests -j ROBOTEST_FILTER=com.android.settings.deviceinfo.storage
      manual visual
Change-Id: I3ebef5829ef4f806add07f58fa02520804768be5

src/com/android/settings/deviceinfo/storage/SecondaryUserController.java

@@ -53,9 +53,11 @@ public class SecondaryUserController extends AbstractPreferenceController implem
     UserInfo mUser;
     private @Nullable
     StorageItemPreference mStoragePreference;
+    private PreferenceGroup mPreferenceGroup;
     private Drawable mUserIcon;
     private long mSize;
     private long mTotalSizeBytes;
+    private boolean mIsVisible;
 
     /**
      * Adds the appropriate controllers to a controller list for handling all secondary users on
@@ -115,16 +117,15 @@ public class SecondaryUserController extends AbstractPreferenceController implem
         if (mStoragePreference == null) {
             mStoragePreference = new StorageItemPreference(screen.getContext());
 
-            PreferenceGroup group =
-                    screen.findPreference(TARGET_PREFERENCE_GROUP_KEY);
+            mPreferenceGroup = screen.findPreference(TARGET_PREFERENCE_GROUP_KEY);
             mStoragePreference.setTitle(mUser.name);
             mStoragePreference.setKey(PREFERENCE_KEY_BASE + mUser.id);
             if (mSize != SIZE_NOT_SET) {
                 mStoragePreference.setStorageSize(mSize, mTotalSizeBytes);
             }
 
-            group.setVisible(true);
-            group.addPreference(mStoragePreference);
+            mPreferenceGroup.setVisible(mIsVisible);
+            mPreferenceGroup.addPreference(mStoragePreference);
             maybeSetIcon();
         }
     }
@@ -168,6 +169,18 @@ public class SecondaryUserController extends AbstractPreferenceController implem
         mTotalSizeBytes = totalSizeBytes;
     }
 
+    /**
+     * Sets visibility of the PreferenceGroup of secondary user.
+     *
+     * @param visible Visibility of the PreferenceGroup.
+     */
+    public void setPreferenceGroupVisible(boolean visible) {
+        mIsVisible = visible;
+        if (mPreferenceGroup != null) {
+            mPreferenceGroup.setVisible(mIsVisible);
+        }
+    }
+
     @Override
     public void handleResult(SparseArray<StorageAsyncLoader.StorageResult> stats) {
         final StorageAsyncLoader.StorageResult result = stats.get(getUser().id);