Experiment compatibility fix: OBU_SIZING and OBU_NO_IVF.

Make OBU_SIZING and OBU_NO_IVF work when combined. Correct the
support for OBUs with LEB128 size fields in obudec.c.

In addition: explicitly disallow pipe input of Annex B OBU without
framing (this implementation requires seeking backwards to function).

Change-Id: I331371f51cae7752a9b1fc091174fe32816ea027
diff --git a/aom/aom_integer.h b/aom/aom_integer.h
index 6aa0c11..5638c64 100644
--- a/aom/aom_integer.h
+++ b/aom/aom_integer.h
@@ -83,7 +83,7 @@
 
 // Returns 0 on success, -1 on decode failure.
 // On success, 'value' stores the decoded LEB128 value and 'length' stores
-// the number of bytes decoded
+// the number of bytes decoded.
 int aom_uleb_decode(const uint8_t *buffer, size_t available, uint64_t *value,
                     size_t *length);