This moves more of HashMap/FnvHashMap to FxHashmap. Again we only
changed instances that do not look security related and have small keys.
Additionally, allocator used the fnv feature which did not seem to be
used.
Testing: Unit Tests and WPT should cover this and functionality change
is highly unlikely.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
Add an off-by-default allocator mode that tracks all live allocations
with sizes and associated stack traces. We also track if each allocation
is visited as part of a measuring heap usage in `about:memory`, allowing
us to report on allocations that are not tracked yet. Right now the list
of untracked allocations is dumped to stdout; I have a python script
coming in a separate PR which makes it easier to perform analysis on the
massive output.
Testing: Manually tested with `./mach build -d --features
servo_allocator/allocation-tracking` and visiting about:memory.
Part of: #11559
---------
Signed-off-by: Josh Matthews <josh@joshmatthews.net>
