Invocation metrics tab doesn't include Subworkflows

[Delphine-L]

Describe the bug
I am using a workflow containing subworkflows, and some of the most time/memory consuming steps are in a subworkflow. However subworkflows don't appear in the metrics tab of the workflow invocation and so they are not very useful.

Galaxy Version and/or server at which you observed the bug
Galaxy Version: {"version_major":"24.2","version_minor":"rc1"}

Browser and Operating System
Operating System: macOS
Browser: Chrome

To Reproduce
Example https://usegalaxy.org/workflows/invocations/8788efd6d3cb3abd

• most consuming steps are in the "trimming and aligning HiC reads" subworkflow

Expected behavior
We should be able to get the tools in the subworkflow as well as the rest of the tool in the invocation metrics. If not at least the overall time/memory for the subworkflow?