Auto merge of #17493 - froydnj:rust-117-fixes, r=jdm

remove various things now that Rust 1.17 is required

std::ptr::eq and Arc::ptr_eq are now usuable, and we can replace a
panic!() with abort().

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because they are trivial replacements.

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1 files changed, 0 insertions, 8 deletions

diff --git a/components/layout/lib.rs b/components/layout/lib.rs
index de8f4755eeb..0b961550974 100644
--- a/components/layout/lib.rs
+++ b/components/layout/lib.rs
@@ -92,14 +92,6 @@ pub use fragment::Fragment;
 pub use fragment::SpecificFragmentInfo;
 pub use self::data::LayoutData;
 
-/// Returns whether the two arguments point to the same value.
-///
-/// FIXME: Remove this and use Arc::ptr_eq once we require Rust 1.17
-#[inline]
-pub fn arc_ptr_eq<T: 'static>(a: &::std::sync::Arc<T>, b: &::std::sync::Arc<T>) -> bool {
-    ::style::ptr_eq::<T>(&**a, &**b)
-}
-
 // We can't use stylearc for everything in layout, because the Flow stuff uses
 // weak references.
 use style::stylearc::Arc as StyleArc;