Convert instant search messages to Mojo

chrome/common/search/mock_searchbox.cc

Index: chrome/common/search/mock_searchbox.cc
diff --git a/chrome/browser/resources/chromeos/login/unrecoverable_cryptohome_error_card.js b/chrome/common/search/mock_searchbox.cc
similarity index 55%
copy from chrome/browser/resources/chromeos/login/unrecoverable_cryptohome_error_card.js
copy to chrome/common/search/mock_searchbox.cc
index 4a35d7a1f18f491bdc0f8d8fa15085b26da20d53..a6412a36517374a7b8d6193a4490ff4e3569ccbb 100644
--- a/chrome/browser/resources/chromeos/login/unrecoverable_cryptohome_error_card.js
+++ b/chrome/common/search/mock_searchbox.cc
@@ -2,10 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-Polymer({
-  is: 'unrecoverable-cryptohome-error-card',
+#include "chrome/common/search/mock_searchbox.h"
 
-  onContinueClicked_: function() {
-    this.fire('done');
-  },
-});
+MockSearchBox::MockSearchBox() = default;
+MockSearchBox::~MockSearchBox() = default;