Give users a way to eval instances of the application.

[polina-c]

When we show sets of instances or instances to user on memory page, we want them to be able to identify the instances in the application.

This is applicable to memory Profile, Leak detection and Diffing features.

We want to utilize existing dev console widgets.

[polina-c]

Subtasks:

• Figure out how observatory is doing it
• Prototype: https://github.com/polina-c/devtools/blob/5f81d000455915277c00e81af497d3c8c0e9555b/packages/devtools_app/lib/src/screens/memory/panes/draft/draft_pane.dart

[polina-c]

This feature is "sort of" supported in the existing analysis view and that we will be removing that functionality when we retire the analysis tab. So it should be recreated in a better form.

[polina-c]

go/observatory-heap-query-walk-through