Repository: flutter
Issue: Stack filter should collapse tree walks
Labels: c: new feature,framework,P3,team-framework,triaged-framework

This kind of thing:

```
I/flutter : #6      MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #7      Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #8      Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #9      ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #10     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #11     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #12     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #13     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #14     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart)
I/flutter : #15     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #16     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #17     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #18     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #19     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #20     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #21     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #22     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #23     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #24     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #25     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #26     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #27     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #28     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #29     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #30     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #31     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #32     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #33     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #34     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #35     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart)
I/flutter : #36     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #37     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #38     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #39     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
I/flutter : #40     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart)
I/flutter : #41     ComponentElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #42     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart)
I/flutter : #43     Element.inflateWidget (package:flutter/src/widgets/framework.dart)
I/flutter : #44     Element.updateChild (package:flutter/src/widgets/framework.dart)
I/flutter : #45     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart)
```

...isn't exactly redundant, but it'd be nice if we could output something cleaner and easier to understand. Right now we often end up with hundreds of stack frames with this kind of thing.