Revert "Added support for AVIF"

This reverts commit 03e2013ab1.

app/src/main/java/eu/faircode/email/DB.java

@@ -427,9 +427,6 @@ public abstract class DB extends RoomDatabase {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
             for (String img : ImageHelper.IMAGE_TYPES8)
                 image.add("'" + img + "'");
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
-            for (String img : ImageHelper.IMAGE_TYPES12)
-                image.add("'" + img + "'");
         String images = TextUtils.join(",", image);
 
         db.execSQL("CREATE TRIGGER IF NOT EXISTS attachment_insert" +

app/src/main/java/eu/faircode/email/ImageHelper.java

@@ -109,20 +109,11 @@ class ImageHelper {
             "image/heif"
     ));
 
-    // https://developer.android.com/about/versions/12/features#avif
-    static final List<String> IMAGE_TYPES12 = Collections.unmodifiableList(Arrays.asList(
-            "image/avif"
-    ));
-
     static boolean isImage(String mimeType) {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
             if (IMAGE_TYPES8.contains(mimeType))
                 return true;
 
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
-            if (IMAGE_TYPES12.contains(mimeType))
-                return true;
-
         return IMAGE_TYPES.contains(mimeType);
     }