cmd/trace: common up the mmu page and add it to cmd/trace/v2
This change moves the MMU HTTP handlers and functionality into the
traceviewer package, since unlike the goroutine pages the vast majority
of that functionality is identical between v1 and v2. This change
involves some refactoring so that callers can plug in their own mutator
utilization computation functions (which is the only point of difference
between v1 and v2). The new interface isn't especially nice, but part of
the problem is the MMU handlers depend on specific endpoints to exist. A
follow-up CL will clean this up a bit.
Like the previous CL did for goroutine analysis, modify the v2 mutator
utilization API to accept a slice of trace events. Again, we might as
well reuse what was already parsed and will be needed for other
purposes. It also simplifies the API slightly.
For #60773.
For #63960.
Change-Id: I6c21ec8d1bf7e95eff5363d0e0005c9217fa00e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/541258
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>