Drop support for decryption

This is a leftover from prior to media source extensions.
Decryption in Chrome doesn't use this path.

Change-Id: I95e07b5c93c380895bf017c7ebca4b2a0ca84949
diff --git a/test/binary_codes_test.cc b/test/binary_codes_test.cc
index 30599fc..42610ea 100644
--- a/test/binary_codes_test.cc
+++ b/test/binary_codes_test.cc
@@ -60,7 +60,7 @@
   }
   aom_stop_encode(&bw);
   aom_reader br;
-  aom_reader_init(&br, bw_buffer, bw.pos, NULL, NULL);
+  aom_reader_init(&br, bw_buffer, bw.pos);
   GTEST_ASSERT_GE(aom_reader_tell(&br), 0u);
   GTEST_ASSERT_LE(aom_reader_tell(&br), 1u);
   for (int n = 0; n < kRanges; ++n) {