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

content/child/webcrypto/status.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/webcrypto/status.h"
 
 #include "base/format_macros.h"
 #include "base/strings/stringprintf.h"
 
 namespace content {
@@ skipping 234 matching lines @@
   return Status(blink::WebCryptoErrorTypeData,
                 "Invalid key length: it is either zero or not a multiple of 8 "
                 "bits");
 }
 
 Status Status::ErrorCreateKeyBadUsages() {
   return Status(blink::WebCryptoErrorTypeSyntax,
                 "Cannot create a key using the specified key usages.");
 }
 
+Status Status::ErrorCreateKeyEmptyUsages() {
+  return Status(blink::WebCryptoErrorTypeSyntax,
+                "Usages cannot be empty when creating a key.");
+}
+
 Status Status::ErrorImportedEcKeyIncorrectCurve() {
   return Status(
       blink::WebCryptoErrorTypeData,
       "The imported EC key specifies a different curve than requested");
 }
 
 Status Status::ErrorJwkIncorrectCrv() {
   return Status(
       blink::WebCryptoErrorTypeData,
       "The JWK's \"crv\" member specifies a different curve than requested");
@@ skipping 21 matching lines @@
       error_type_(error_type),
       error_details_(error_details_utf8) {
 }
 
 Status::Status(Type type) : type_(type) {
 }
 
 }  // namespace webcrypto
 
 }  // namespace content