Update the API usage to get total size of devices

StorageStatsManager fixed in StorageStatsService#getTotalBytes
So that we should change back to call the API.

Bug: 295358118
Bug: 288103116
Test: verified manually
Change-Id: I3dcc9698403612f961cf0de41925dcbcb43e260b

src/com/android/settings/Utils.java

@@ -66,7 +66,6 @@ import android.os.BatteryManager;
 import android.os.Binder;
 import android.os.Build;
 import android.os.Bundle;
-import android.os.Environment;
 import android.os.IBinder;
 import android.os.INetworkManagementService;
 import android.os.RemoteException;
@@ -1354,14 +1353,4 @@ public final class Utils extends com.android.settingslib.Utils {
         return dreamsSupported && (!dreamsOnlyEnabledForDockUser || canCurrentUserDream(context));
     }
 
-    /**
-     * Get private total size directly.
-     * Referred from StorageManager
-     */
-    public static long getPrimaryStorageSize() {
-        // TODO(b/288103116): remove this method once support by StorageManager.
-        return Environment.getDataDirectory().getTotalSpace()
-                + Environment.getRootDirectory().getTotalSpace();
-    }
-
 }