Add encoder/decoder mismatch information to internal stats file.

Change-Id: Ibb6ba26e8718d3af27553ca59443a8c6aec7749d
diff --git a/vpxenc.c b/vpxenc.c
index 26c52d5..625977a 100644
--- a/vpxenc.c
+++ b/vpxenc.c
@@ -2103,12 +2103,26 @@
   }
 
   if (test_decode) {
+#if CONFIG_INTERNAL_STATS
+    FILE *f = fopen("opsnr.stt", "a");
+#endif
     fprintf(stderr, "\n");
-    if (enc_dec_match)
+    if (enc_dec_match) {
       fprintf(stderr, "No mismatch detected in recon buffers\n");
-    else
+#if CONFIG_INTERNAL_STATS
+      fprintf(f, "No mismatch detected in recon buffers\n");
+#endif
+    } else {
       fprintf(stderr, "First mismatch occurred in frame %d\n",
               first_bad_frame);
+#if CONFIG_INTERNAL_STATS
+      fprintf(f, "First mismatch occurred in frame %d\n",
+              first_bad_frame);
+#endif
+    }
+#if CONFIG_INTERNAL_STATS
+    fclose(f);
+#endif
   }
 
   if (show_q_hist_buckets)