Renaming WhichPreview following the camal case (2/3)

Test: Build success
Bug: 315850406
Flag: ACONFIG com.android.wallpaper.multi_crop_preview_ui_flag DEVELOPMENT
Change-Id: If7c143c2d2c887cd941aedbfdf874aeac7277638
diff --git a/src/com/android/customization/picker/WallpaperPreviewer.java b/src/com/android/customization/picker/WallpaperPreviewer.java
index d74bfae..18bc89c 100644
--- a/src/com/android/customization/picker/WallpaperPreviewer.java
+++ b/src/com/android/customization/picker/WallpaperPreviewer.java
@@ -241,7 +241,7 @@
                                                 () -> mFadeInScrim.setVisibility(View.INVISIBLE));
                             }
                         }
-                    }, mWallpaperSurface, WallpaperConnection.WHICH_PREVIEW.PREVIEW_CURRENT);
+                    }, mWallpaperSurface, WallpaperConnection.WhichPreview.PREVIEW_CURRENT);
 
             mWallpaperConnection.setVisibility(true);
             mHomePreview.post(() -> {