Check that usage isn't empty when generateKey() is called

content/child/webcrypto/openssl/rsa_key_openssl.cc

Index: content/child/webcrypto/openssl/rsa_key_openssl.cc
diff --git a/content/child/webcrypto/openssl/rsa_key_openssl.cc b/content/child/webcrypto/openssl/rsa_key_openssl.cc
index 49f57e729e1d2a60ac3d175726a121e9a30abfcf..09e277f261f71d910379228d3f4921c0faa2160f 100644
--- a/content/child/webcrypto/openssl/rsa_key_openssl.cc
+++ b/content/child/webcrypto/openssl/rsa_key_openssl.cc
@@ -167,6 +167,9 @@ Status RsaHashedAlgorithm::GenerateKey(
   const blink::WebCryptoKeyUsageMask private_usages =
       combined_usages & all_private_key_usages_;
 
+  if (private_usages == 0)
+    return Status::ErrorCreateKeyEmptyUsages();
+
   const blink::WebCryptoRsaHashedKeyGenParams* params =
       algorithm.rsaHashedKeyGenParams();