This adds support for encrypted ONC import

crypto/hmac.h

Index: crypto/hmac.h
diff --git a/crypto/hmac.h b/crypto/hmac.h
index b170ce75fa0e4d185c3988d28b9508e903a09af6..0abbb98b87acae40966453df25c233e1d5fcd689 100644
--- a/crypto/hmac.h
+++ b/crypto/hmac.h
@@ -19,6 +19,7 @@ namespace crypto {
 
 // Simplify the interface and reduce includes by abstracting out the internals.
 struct HMACPlatformData;
+class SymmetricKey;
 
 class CRYPTO_EXPORT HMAC {
  public:
@@ -41,6 +42,10 @@ class CRYPTO_EXPORT HMAC {
   // TODO(abarth): key_length should be a size_t.
   bool Init(const unsigned char* key, int key_length) WARN_UNUSED_RESULT;
 
+  // Initializes this instance using |key|. Call Init
+  // only once. It returns false on the second or later calls.
+  bool Init(SymmetricKey* key) WARN_UNUSED_RESULT;
+
   // Initializes this instance using |key|. Call Init only once. It returns
   // false on the second or later calls.
   bool Init(const base::StringPiece& key) WARN_UNUSED_RESULT {