Auto merge of #18938 - nnethercote:bug-1409255, r=SimonSapin

Replace all uses of the `heapsize` crate with `malloc_size_of`.

Servo currently uses `heapsize`, but Stylo/Gecko use `malloc_size_of`.
`malloc_size_of` is better -- it handles various cases that `heapsize` does not
-- so this patch changes Servo to use `malloc_size_of`.

This patch makes the following changes to the `malloc_size_of` crate.

- Adds `MallocSizeOf` trait implementations for numerous types, some built-in
  (e.g. `VecDeque`), some external and Servo-only (e.g. `string_cache`).

- Makes `enclosing_size_of_op` optional, because vanilla jemalloc doesn't
  support that operation.

- For `HashSet`/`HashMap`, falls back to a computed estimate when
  `enclosing_size_of_op` isn't available.

- Adds an extern "C" `malloc_size_of` function that does the actual heap
  measurement; this is based on the same functions from the `heapsize` crate.

This patch makes the following changes elsewhere.

- Converts all the uses of `heapsize` to instead use `malloc_size_of`.

- Disables the "heapsize"/"heap_size" feature for the external crates that
  provide it.

- Removes the `HeapSizeOf` implementation from `hashglobe`.

- Adds `ignore` annotations to a few `Rc`/`Arc`, because `malloc_size_of`
  doesn't derive those types, unlike `heapsize`.

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---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1409255

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because testing is on the Gecko side.

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1 files changed, 3 insertions, 2 deletions

diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 4963b57c3aa..f397ef42148 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -36,12 +36,13 @@ pub type TrustedWorkerAddress = Trusted<Worker>;
 #[dom_struct]
 pub struct Worker {
     eventtarget: EventTarget,
-    #[ignore_heap_size_of = "Defined in std"]
+    #[ignore_malloc_size_of = "Defined in std"]
     /// Sender to the Receiver associated with the DedicatedWorkerGlobalScope
     /// this Worker created.
     sender: Sender<(TrustedWorkerAddress, WorkerScriptMsg)>,
+    #[ignore_malloc_size_of = "Arc"]
     closing: Arc<AtomicBool>,
-    #[ignore_heap_size_of = "Defined in rust-mozjs"]
+    #[ignore_malloc_size_of = "Defined in rust-mozjs"]
     runtime: Arc<Mutex<Option<SharedRt>>>,
     terminated: Cell<bool>,
 }