Bug 1049434 - Don't allocate SECItems with new operator r=rbarnes

dom/crypto/CryptoBuffer.cpp

@@ -5,6 +5,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "CryptoBuffer.h"
+#include "secitem.h"
 #include "mozilla/Base64.h"
 #include "mozilla/dom/UnionTypes.h"
 
@@ -150,7 +151,7 @@ CryptoBuffer::ToSECItem() const
     return nullptr;
   }
 
-  SECItem* item = new SECItem();
+  SECItem* item = ::SECITEM_AllocItem(nullptr, nullptr, 0);
   item->type = siBuffer;
   item->data = data;
   item->len = Length();

dom/crypto/CryptoKey.cpp

@@ -560,7 +560,11 @@ bool ReadAndEncodeAttribute(SECKEYPrivateKey* aKey,
                             CK_ATTRIBUTE_TYPE aAttribute,
                             Optional<nsString>& aDst)
 {
-  ScopedSECItem item(new SECItem());
+  ScopedSECItem item(::SECITEM_AllocItem(nullptr, nullptr, 0));
+  if (!item) {
+    return false;
+  }
+
   if (PK11_ReadRawAttribute(PK11_TypePrivKey, aKey, aAttribute, item)
         != SECSuccess) {
     return false;