Remove associated keying material when unregistering from GCM

components/gcm_driver/crypto/gcm_encryption_provider.cc

Index: components/gcm_driver/crypto/gcm_encryption_provider.cc
diff --git a/components/gcm_driver/crypto/gcm_encryption_provider.cc b/components/gcm_driver/crypto/gcm_encryption_provider.cc
index 2da9a458da9f466a87aae85d585aeecddeeb6917..bb6d4ab441a0194263ac8200dc64f433eb751f64 100644
--- a/components/gcm_driver/crypto/gcm_encryption_provider.cc
+++ b/components/gcm_driver/crypto/gcm_encryption_provider.cc
@@ -82,6 +82,13 @@ void GCMEncryptionProvider::GetEncryptionInfo(
                          weak_ptr_factory_.GetWeakPtr(), app_id, callback));
 }
 
+void GCMEncryptionProvider::RemoveEncryptionInfo(
+    const std::string& app_id,
+    const base::Closure& callback) {
+  DCHECK(key_store_);
+  key_store_->RemoveKeys(app_id, callback);
+}
+
 bool GCMEncryptionProvider::IsEncryptedMessage(const IncomingMessage& message)
     const {
   // The Web Push protocol requires the encryption and crypto-key properties to