Implement HKDF for webcrypto

content/child/webcrypto/algorithm_registry.cc

Index: content/child/webcrypto/algorithm_registry.cc
diff --git a/content/child/webcrypto/algorithm_registry.cc b/content/child/webcrypto/algorithm_registry.cc
index eeef315d40c83bd5a9f6d19337d6d0adb0f25e04..e45ec59902e069ffdebc97bef7ca649a95fb424d 100644
--- a/content/child/webcrypto/algorithm_registry.cc
+++ b/content/child/webcrypto/algorithm_registry.cc
@@ -29,7 +29,8 @@ class AlgorithmRegistry {
         rsa_oaep_(CreatePlatformRsaOaepImplementation()),
         rsa_pss_(CreatePlatformRsaPssImplementation()),
         ecdsa_(CreatePlatformEcdsaImplementation()),
-        ecdh_(CreatePlatformEcdhImplementation()) {
+        ecdh_(CreatePlatformEcdhImplementation()),
+        hkdf_(CreatePlatformHkdfImplementation()) {
     PlatformInit();
   }
 
@@ -61,6 +62,8 @@ class AlgorithmRegistry {
         return ecdsa_.get();
       case blink::WebCryptoAlgorithmIdEcdh:
         return ecdh_.get();
+      case blink::WebCryptoAlgorithmIdHkdf:
+        return hkdf_.get();
       default:
         return NULL;
     }
@@ -78,6 +81,7 @@ class AlgorithmRegistry {
   const scoped_ptr<AlgorithmImplementation> rsa_pss_;
   const scoped_ptr<AlgorithmImplementation> ecdsa_;
   const scoped_ptr<AlgorithmImplementation> ecdh_;
+  const scoped_ptr<AlgorithmImplementation> hkdf_;
 };
 
 }  // namespace