allow updating array/object-based prop type using same array/object

Description:

I'd like to be able to update an array property type using the same array without having the clone the object myself to get past the component deepEqual check.

// test component
schema: {
  foo: {type: 'array'}
}

var foo = el.getAttribute('test').foo;
foo.push(50);
el.setAttribute('test', 'foo', foo);

Currently I need to do:

var foo = el.getAttribute('test').foo;
foo.push(50);
el.setAttribute('test', 'foo', AFRAME.utils.clone(foo));

Possible solutions:

// Skip equals check flag or force update flag.
el.setAttribute('test', 'foo', foo, true)

// Options object for setAttribute
el.setAttribute('test', {foo: foo}, {forceUpdate: true, clobber: false});

• Clone the object/array when setting oldData, but this doesn't sound great for perf.

Start at the component setAttribute path and the deepEqual check described in the issue. Trace how array and object prop values are compared and how old values are stored, then determine how a same-reference update should be recognized without changing unrelated setAttribute behavior. Done means the example updates foo after push without requiring AFRAME.utils.clone(foo), with coverage for array and object props.