MP4: limit extent_count in iloc box.

ItemLoc::getLoc() has a CHECK for extents.size() == 1.

Test: poc & MediaMetadataRetrieverTest
Bug: 124389881
Change-Id: Ic45cafb8ce47aea106aabdffeccd031b446579b2
diff --git a/media/extractors/mp4/ItemTable.cpp b/media/extractors/mp4/ItemTable.cpp
index d56abaa..8c8e6d1 100644
--- a/media/extractors/mp4/ItemTable.cpp
+++ b/media/extractors/mp4/ItemTable.cpp
@@ -426,10 +426,8 @@
         }
         ALOGV("extent_count %d", extent_count);
 
-        if (extent_count > 1 && (offset_size == 0 || length_size == 0)) {
-            // if the item is dividec into more than one extents, offset and
-            // length must be present.
-            return ERROR_MALFORMED;
+        if (extent_count > 1) {
+            return ERROR_UNSUPPORTED;
         }
         offset += 2;