Increment num_boxes if !ftyp in stream API

Change-Id: I22c46d82d967ae7d154e1600ecf6e96c1589a7d6

avifinfo.c

diff --git a/avifinfo.c b/avifinfo.c
index 758130e..a8a0272 100644
--- a/avifinfo.c
+++ b/avifinfo.c
@@ -718,6 +718,14 @@
     AVIFINFO_CHECK_FOUND(AvifInfoInternalParseBox(
         /*nesting_level=*/0, stream, AVIFINFO_MAX_SIZE, num_parsed_boxes,
         &box));
+    if (*num_parsed_boxes == 1 && memcmp(box.type, "ftyp", 4)) {
+      // AvifInfoGetFeaturesStream() can be called on a full stream or on a
+      // stream where the 'ftyp' box was already read. If it is not the first
+      // parsed box here, consider it was, so that this function returns the
+      // same status in both situations (because of the AVIFINFO_MAX_NUM_BOXES
+      // check that would compare a different box count otherwise).
+      ++*num_parsed_boxes;
+    }
     if (!memcmp(box.type, "meta", 4)) {
       return ParseMeta(/*nesting_level=*/1, stream, box.content_size,
                        num_parsed_boxes, features);