Bug 996899 - Calling CustomizableUI.registerArea with an altered 'legacy', 'overflowable', or 'type' should throw. r=mconley

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rename : browser/components/customizableui/test/browser_996364_defaultCollapsed.js => browser/components/customizableui/test/browser_996364_registerArea_different_properties.js
extra : rebase_source : bb2febcf3f47a0a7bb5f7ea3f2fe14b3d6e6e8f2
Bug 985509 - Edit Bookmark panel button doesn't have an open state. r=mconley

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extra : rebase_source : 7b8ccb4da59629dda5102be02e4ec6eee219dc2a