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 e849f0d81babbe9c0ae1834975f3c96a4ba8b564..d3c38e8e2f51ad2e562a87ab2f4fc7f67680ec6c 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();