public static final class StandardTags.RootTag extends Tag
Frame.getArguments() into FrameSlots, it should do it here for the
instrumentation to work correctly.
Use case descriptions:
identifier "ROOT". A node tagged
with StandardTags.RootTag must provide a source section, if its
root node provides a source section.
If the a node tagged with root returns a non null value then it
must be an interop value. There are assertions in place verifying this when Java assertions
are enabled (-ea).
Tag.Identifier