Auto merge of #15650 - Greeene:rm_array_buffer_contents_trait, r=SimonSapin

Remove ArrayBufferViewContents trait

<!-- Please describe your changes on the following line: -->
Removed ArrayBufferViewContents trait and dependent uses.

---
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- [ x ] `./mach build -d` does not report any errors
- [ x ] `./mach test-tidy` does not report any errors
- [ x ] These changes fix #15551

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- [ x ] These changes do not require tests because it's just unused trait and @jdm said, "No need for automated tests; if the build succeeds, it's good enough for a PR."

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components/script/dom/bindings/conversions.rs

@@ -50,10 +50,7 @@ use js::glue::{RUST_JSID_IS_STRING, RUST_JSID_TO_STRING, UnwrapObject};
 use js::jsapi::{HandleId, HandleObject, HandleValue, JSContext, JSObject, JSString};
 use js::jsapi::{JS_GetLatin1StringCharsAndLength, JS_GetReservedSlot};
 use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_IsArrayObject};
-use js::jsapi::{JS_NewFloat32Array, JS_NewFloat64Array, JS_NewInt8Array};
-use js::jsapi::{JS_NewInt16Array, JS_NewInt32Array, JS_NewStringCopyN};
-use js::jsapi::{JS_NewUint8Array, JS_NewUint16Array, JS_NewUint32Array};
-use js::jsapi::{JS_StringHasLatin1Chars, MutableHandleValue, Type};
+use js::jsapi::{JS_NewStringCopyN, JS_StringHasLatin1Chars, MutableHandleValue};
 use js::jsval::{ObjectValue, StringValue};
 use js::rust::{ToString, get_object_class, is_dom_class, is_dom_object, maybe_wrap_value};
 use libc;
@@ -476,99 +473,6 @@ impl<T: DomObject> ToJSValConvertible for Root<T> {
     }
 }
 
-/// A JS ArrayBufferView contents can only be viewed as the types marked with this trait
-pub unsafe trait ArrayBufferViewContents: Clone {
-    /// Check if the JS ArrayBufferView type is compatible with the implementor of the
-    /// trait
-    fn is_type_compatible(ty: Type) -> bool;
-
-    /// Creates a typed array
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject;
-}
-
-unsafe impl ArrayBufferViewContents for u8 {
-    fn is_type_compatible(ty: Type) -> bool {
-        match ty {
-            Type::Uint8 |
-            Type::Uint8Clamped => true,
-            _ => false,
-        }
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewUint8Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for i8 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Int8 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewInt8Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for u16 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Uint16 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewUint16Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for i16 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Int16 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewInt16Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for u32 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Uint32 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewUint32Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for i32 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Int32 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewInt32Array(cx, num)
-    }
-}
-
-unsafe impl ArrayBufferViewContents for f32 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Float32 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewFloat32Array(cx, num)
-    }
-}
-unsafe impl ArrayBufferViewContents for f64 {
-    fn is_type_compatible(ty: Type) -> bool {
-        ty as i32 == Type::Float64 as i32
-    }
-
-    unsafe fn new(cx: *mut JSContext, num: u32) -> *mut JSObject {
-        JS_NewFloat64Array(cx, num)
-    }
-}
-
 /// Returns whether `value` is an array-like object.
 /// Note: Currently only Arrays are supported.
 /// TODO: Expand this to support sequences and other array-like objects