Revert "Revert "external/boringssl: sync with upstream.""

This reverts commit a04d78d392463df4e69a64360c952ffa5abd22f7.

Underlying issue was fixed.

Change-Id: I49685b653d16e728eb38e79e02b2c33ddeefed88
diff --git a/src/crypto/test/file_test.h b/src/crypto/test/file_test.h
index 7303d8a..24651ab 100644
--- a/src/crypto/test/file_test.h
+++ b/src/crypto/test/file_test.h
@@ -18,11 +18,19 @@
 #include <stdint.h>
 #include <stdio.h>
 
+#if defined(_MSC_VER)
+#pragma warning(push)
+#pragma warning(disable: 4702)
+#endif
+
 #include <string>
 #include <map>
 #include <set>
 #include <vector>
 
+#if defined(_MSC_VER)
+#pragma warning(pop)
+#endif
 
 // File-based test framework.
 //