Include BoringSSL headers from third_party/ in crypto.

crypto/symmetric_key_openssl.cc

Index: crypto/symmetric_key_openssl.cc
diff --git a/crypto/symmetric_key_openssl.cc b/crypto/symmetric_key_openssl.cc
index 912c9b4db2d7468e822cd8062b87ea87432bd16f..76ec969e901aeab45c68168a205d508467109528 100644
--- a/crypto/symmetric_key_openssl.cc
+++ b/crypto/symmetric_key_openssl.cc
@@ -4,15 +4,14 @@
 
 #include "crypto/symmetric_key.h"
 
-#include <openssl/evp.h>
-#include <openssl/rand.h>
-
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_util.h"
 #include "crypto/openssl_util.h"
+#include "third_party/boringssl/src/include/openssl/evp.h"
+#include "third_party/boringssl/src/include/openssl/rand.h"
 
 namespace crypto {