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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- [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, 3 deletions

diff --git a/components/script/dom/bindings/str.rs b/components/script/dom/bindings/str.rs
index b665b64da8a..af33f662ff7 100644
--- a/components/script/dom/bindings/str.rs
+++ b/components/script/dom/bindings/str.rs
@@ -19,7 +19,7 @@ use std::str;
 use std::str::{Bytes, FromStr};
 
 /// Encapsulates the IDL `ByteString` type.
-#[derive(Clone, Debug, Default, Eq, HeapSizeOf, JSTraceable, PartialEq)]
+#[derive(Clone, Debug, Default, Eq, JSTraceable, MallocSizeOf, PartialEq)]
 pub struct ByteString(Vec<u8>);
 
 impl ByteString {
@@ -78,7 +78,7 @@ impl ops::Deref for ByteString {
 
 /// A string that is constructed from a UCS-2 buffer by replacing invalid code
 /// points with the replacement character.
-#[derive(Clone, Default, HeapSizeOf)]
+#[derive(Clone, Default, MallocSizeOf)]
 pub struct USVString(pub String);
 
 
@@ -153,7 +153,7 @@ pub fn is_token(s: &[u8]) -> bool {
 ///
 /// This type is currently `!Send`, in order to help with an independent
 /// experiment to store `JSString`s rather than Rust `String`s.
-#[derive(Clone, Debug, Eq, Hash, HeapSizeOf, Ord, PartialEq, PartialOrd)]
+#[derive(Clone, Debug, Eq, Hash, MallocSizeOf, Ord, PartialEq, PartialOrd)]
 pub struct DOMString(String, PhantomData<*const ()>);
 
 impl DOMString {