global binding group

[tanhauhau]

an alternative to #4881

a different attempt to #2308

using a global weak map, taking the array as key to the map, to store different binding group.

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Tests

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[Conduitry]

WeakMap does appear to be supported in IE11, but not in older versions - and it's not something that it's possible to polyfill correctly. I'm hesitant about whether this would be an acceptable change.