Bug 1746349 - Add a test to verify that the window.name won't reset if document.domain was set. r=smaug This patch adds a test in the web-platform test clear-window-name.https.html. The test will load the sub domain and set the document.domain to the parent domain. And verify that the window.name won't be reset after navigating to the sub domain. Depends on D143994 Differential Revision: https://phabricator.services.mozilla.com/D154786

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