external/boringssl: Sync to 8625ec4b436ccb4098ed4aac10891eff8372be41.

This includes the following changes:

https://boringssl.googlesource.com/boringssl/+log/c596415ec62b501523d80f9afa26b135406da6bf..8625ec4b436ccb4098ed4aac10891eff8372be41

Test: cts -m CtsLibcoreTestCases
Change-Id: I47a45e6b6f46b19fcbcb6c917895867d56dcd2ca
diff --git a/src/crypto/test/test_util.cc b/src/crypto/test/test_util.cc
index 493b124..4ad777f 100644
--- a/src/crypto/test/test_util.cc
+++ b/src/crypto/test/test_util.cc
@@ -30,6 +30,10 @@
 }
 
 std::ostream &operator<<(std::ostream &os, const Bytes &in) {
+  if (in.len == 0) {
+    return os << "<empty Bytes>";
+  }
+
   // Print a byte slice as hex.
   static const char hex[] = "0123456789abcdef";
   for (size_t i = 0; i < in.len; i++) {