Bug 1593845 - Ensure picture cache dirty rect is clamped to tile rect. r=sotaro
Bug 1593845 - Ensure picture cache dirty rect is clamped to tile rect. r=sotaro

Differential Revision: https://phabricator.services.mozilla.com/D52493

[wrupdater] From https://hg.mozilla.org/mozilla-central/rev/e05f10f48f524d429d9eade6ee8d7001ab32061f

servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender