bug 996358 - Add flags to keep tab streaming from going to Beta or Release r=mfinkle

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extra : rebase_source : 8d903784db2a5d15a0ef109ce3143dd1cbb6c4b9
Bug 996159 - Fix sync config section on Windows with 125% DPI. r=gavin
Bug 825427 - Intermittent browser_responsiveruleview.js; r=miker
Bug 986284 - Intermittent browser_inspector_bug_952294_tooltips_dimensions.js; r=miker

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rename : browser/devtools/inspector/test/browser_inspector_bug_952294_tooltips_dimensions.js => browser/devtools/styleinspector/test/browser_styleinspector_tooltip-size.js
 Bug 993985 - Fix broken tooltip in Developer Toolbar; r=mratcliffe