ImageDecoder: add "image/avif" to support list

Test: ImageDecoderTest
Bug: b/252836084
Change-Id: If3a26cfd4f79780ebe3c5710c9e89f09f140fd1a
diff --git a/graphics/java/android/graphics/ImageDecoder.java b/graphics/java/android/graphics/ImageDecoder.java
index 51f99ec..60898ef 100644
--- a/graphics/java/android/graphics/ImageDecoder.java
+++ b/graphics/java/android/graphics/ImageDecoder.java
@@ -914,6 +914,7 @@
             case "image/gif":
             case "image/heif":
             case "image/heic":
+            case "image/avif":
             case "image/bmp":
             case "image/x-ico":
             case "image/vnd.wap.wbmp":