Fix memory leak in opj_j2k_merge_ppt.

third_party/libopenjpeg20/j2k.c

Index: third_party/libopenjpeg20/j2k.c
diff --git a/third_party/libopenjpeg20/j2k.c b/third_party/libopenjpeg20/j2k.c
index 6346c219073818889c62b3b73dc81c594c47b639..7712d38600c2009e2ac557106c1698dd052ea5ed 100644
--- a/third_party/libopenjpeg20/j2k.c
+++ b/third_party/libopenjpeg20/j2k.c
@@ -3807,7 +3807,10 @@ static OPJ_BOOL opj_j2k_merge_ppt(opj_tcp_t *p_tcp, opj_event_mgr_t * p_manager)
 	/* preconditions */
 	assert(p_tcp != 00);
 	assert(p_manager != 00);
-	assert(p_tcp->ppt_buffer == NULL);
+	
+	if(p_tcp->ppt_buffer != NULL) {

[dsinclair, 2016/09/19 12:59:01]

Have we verified this can ever happen? It's a precondition that ppt_buffer is
NULL coming into this method, so the callers should be verifying that the buffer
is NULL before making the call.

Can we take a look at the callers to determine if they are doing this check,
instead of changing the assert here.

+		return OPJ_FALSE;
+	}
 	
 	if (p_tcp->ppt == 0U) {
 		return OPJ_TRUE;