servo: Merge #20389 - getRandomValues uses ArrayBufferView now (from christianpoveda:issue_20350); r=jdm

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- Changed the `Crypto.webidl` file to allow getRandomValues to recieve an ArrayBufferView as input
- Removed unnecesary checks from `crypto.rs` and did the necessary changes to match the `webidl` changes.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20350 (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Source-Repo: https://github.com/servo/servo
Source-Revision: e5b606f6a41058bdcc5745ab0da075d0e6ed52fb

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : cdc7f6e7693960b99ee9bc172f4c73216121da77

servo/components/script/dom/crypto.rs

@@ -12,6 +12,8 @@ use dom::globalscope::GlobalScope;
 use dom_struct::dom_struct;
 use js::jsapi::{JSContext, JSObject};
 use js::jsapi::Type;
+use js::rust::CustomAutoRooterGuard;
+use js::typedarray::ArrayBufferView;
 use servo_rand::{ServoRng, Rng};
 use std::ptr::NonNull;
 
@@ -43,29 +45,21 @@ impl CryptoMethods for Crypto {
     // https://dvcs.w3.org/hg/webcrypto-api/raw-file/tip/spec/Overview.html#Crypto-method-getRandomValues
     unsafe fn GetRandomValues(&self,
                        _cx: *mut JSContext,
-                       input: *mut JSObject)
+                       mut input: CustomAutoRooterGuard<ArrayBufferView>)
                        -> Fallible<NonNull<JSObject>> {
-        assert!(!input.is_null());
-        typedarray!(in(_cx) let mut array_buffer_view: ArrayBufferView = input);
-        let (array_type, mut data) = match array_buffer_view.as_mut() {
-            Ok(x) => (x.get_array_type(), x.as_mut_slice()),
-            Err(_) => {
-                return Err(Error::Type("Argument to Crypto.getRandomValues is not an ArrayBufferView"
-                                       .to_owned()));
-            }
-        };
+        let array_type = input.get_array_type();
 
         if !is_integer_buffer(array_type) {
             return Err(Error::TypeMismatch);
-        }
-
+        } else {
+            let mut data = input.as_mut_slice();
             if data.len() > 65536 {
                 return Err(Error::QuotaExceeded);
             }
-
             self.rng.borrow_mut().fill_bytes(&mut data);
+        }
 
-        Ok(NonNull::new_unchecked(input))
+        Ok(NonNull::new_unchecked(*input.underlying_object()))
     }
 }
 

servo/components/script/dom/webidls/Crypto.webidl

@@ -18,7 +18,6 @@ WorkerGlobalScope implements GlobalCrypto;
 [Exposed=(Window,Worker)]
 interface Crypto {
   //readonly attribute SubtleCrypto subtle;
-  //ArrayBufferView getRandomValues(ArrayBufferView array);
   [Throws]
-  ArrayBufferView getRandomValues(object array);
+  ArrayBufferView getRandomValues(ArrayBufferView array);
 };