Tree code minor simplification

[Les]

I found some Tree code that can be simplified :)

// Current code
this.getChildren().forEach(function(child){
	dijit._Container.prototype.removeChild.call(this, child);
}, this);

// New code
this.getChildren().forEach(dijit._Container.prototype.removeChild);

// Current code
dojo.forEach(this.getChildren(), function(child, idx){
  child._updateLayout();
});

// New code (removed unused local var idx)
dojo.forEach(this.getChildren(), function(child){
  child._updateLayout();
});

[Les]

I see code in a few place that could be tiny bit shorter. It doesn't amount to much, but the code will be smaller.

dojo.forEach(this.getChildren(), function(child){
	child.attr("indent", indent+1);
});

this.getChildren().forEach(function(child){
	child.attr("indent", indent+1);
});

[bill]

As discussed in #9985 we can't in general depend on getChildren() returning a NodeList rather than a simple array. I guess it's a safe for Tree though, although I am surprised that Tree uses that syntax already.

About:

this.getChildren().forEach(dijit._Container.prototype.removeChild);

Are you sure that "this" will be the correct value (a pointer to the widget) inside of _Container.removeChild()?

Of course removing the unused variable makes sense.

[bill]

Can't depend on getChildren() returning a NodeList, as a matter of fact in 1.5 it doesn't. Maybe that will change for 2.0 in which case we'll update all usages of getChildren(), but for now I'm going to close this ticket.