Tests that the 'getElementById' method for the 'SVGSVGElement' interface is scoped.
Two subtrees of 'svg' elements are used, each with 'rect' elements as children. A reference to the first 'svg' element is obtained via the 'document' element's 'getElementById' method. This reference is used to verify the presence of 'getElementId'. Next, 'getElementById' on the 'SVGSVGElement' reference is used to locate its child element. Then, 'getElementById' attempts to get an element in a neighboring subtree. Finally, an element at the sibling level is attempted to be accessed via 'getElementById'.
The test is passed if there is no red visible on the page.