tools: implement blob close

Implement blob close call.

Change-Id: If7c845e1e3b542e6f0253136eb8b6fd40bc96f3d
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/test/blob_interface_mock.hpp b/test/blob_interface_mock.hpp
index c3b4f4c..eff241f 100644
--- a/test/blob_interface_mock.hpp
+++ b/test/blob_interface_mock.hpp
@@ -14,6 +14,7 @@
     MOCK_METHOD2(openBlob,
                  std::uint16_t(const std::string&,
                                blobs::FirmwareBlobHandler::UpdateFlags));
+    MOCK_METHOD1(closeBlob, void(std::uint16_t));
 };
 
 } // namespace host_tool