This API can be used by app developers that want to diagnose high
memory consumption by dumping state of Dart VM heap at specific
points in their apps code and later analyzing those dumps offline
(e.g. using the tool in `<sdk>/runtime/tools/heapsnapshot`).
TEST=Existing test suite.
Change-Id: I04de6ba564f7b9eaf8b59d41fc4b3ec35ce8d2e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/279972
Reviewed-by: Aske Simon Christensen <askesc@google.com>
Reviewed-by: Michael Thomsen <mit@google.com>
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Reviewed-by: Lasse Nielsen <lrn@google.com>
Reviewed-by: Jacob Richman <jacobr@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Martin Kustermann
e1c2192110