Add retaining_path instance command to VM service, exposed in the Observatory
with a [find] eval-link in instance view. By default shows up to 10 elements,
possibly followed by [find more] which doubles the number of elements shown.
Change RetainingPath to include the object itself.
Always include an id in Object::PrintJSONImpl, to avoid instance-ref crashing on
internal objects.
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org//292663012
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@36516 260f80e4-7a28-3924-810f-c04153c831b5
Features:
* Performs a pre-order, depth-first search.
* Allows the visitor to direct whether to
proceed, backtrack, or abort.
* Provides a complete chain of parents to the root.
(unlike the GC marking stack).
The plan is to use this in the observatory, e.g.:
* inspect a path from the isolate roots to a particular object, or
* determine how much memory is kept alive by some particular object or class of objects.
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org//266643002
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@35711 260f80e4-7a28-3924-810f-c04153c831b5
koda@google.com