[WebCrypto] Throw syntaxError if keyUsage is empty in ImportKey

content/child/webcrypto/webcrypto_util.cc

Index: content/child/webcrypto/webcrypto_util.cc
diff --git a/content/child/webcrypto/webcrypto_util.cc b/content/child/webcrypto/webcrypto_util.cc
index 6dad83fcae7dae6c9cb0bd1ecd7b50139d56c670..aa5d611e0fcea607e6b43376f59e21237fa33331 100644
--- a/content/child/webcrypto/webcrypto_util.cc
+++ b/content/child/webcrypto/webcrypto_util.cc
@@ -229,7 +229,12 @@ Status VerifyAesKeyLengthForImport(unsigned int keylen_bytes) {
 }
 
 Status CheckKeyCreationUsages(blink::WebCryptoKeyUsageMask all_possible_usages,
-                              blink::WebCryptoKeyUsageMask actual_usages) {
+                              blink::WebCryptoKeyUsageMask actual_usages,
+                              bool check_usage) {

[eroman, 2014/12/09 21:04:46]

This is poorly named -- the entire purpose of this function is in fact to check
usages.

|allow_empty_usages| for example would be a better name.

[Habib Virji, 2014/12/15 18:48:56]

Done.

+  // In case import key calls this function, it checks for empty usage

[eroman, 2014/12/09 21:04:46]

This comment is unnecessary (will apply to both importKey and generateKey)

[Habib Virji, 2014/12/15 18:48:56]

Removed

+  if (check_usage && actual_usages == 0)
+    return Status::ErrorImportKeyEmptyUsages();
+
   if (!ContainsKeyUsages(all_possible_usages, actual_usages))
     return Status::ErrorCreateKeyBadUsages();
   return Status::Success();