Does plain object in JavaScript V8 has hidden class?

[ajcv]

I've read hidden class at V8 Design Elements:Fast Property Access.Objects in the example is created by a constructor\[code\]var p1 = new Point(1,2)\[/code\]p1 has a hidden class for fast access it's property 'x', 'y'.\[code\]var p2 = {x:1,y:2}\[/code\]so, my question#1 is: does p2 share a hidden class with p1?and, if p2 do has a hidden class, will following code change the hidden class?\[code\]delete p2.x\[/code\]Here is the article make me ask this question:Writing Fast, Memory-Efficient JavaScriptJust read DE-REFERENCING MISCONCEPTIONS part.Is this article right about deleting property?(question#2)