Auto merge of #23816 - marmeladema:issue-20377, r=jdm

Wrapping unsafe raw JSContext pointers in a safe struct. Part 1.

Wrapping unsafe raw JSContext pointers in a safe struct. Issue #20377.

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<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] create a struct JSContext(*mut jsapi::JSContext) type
- [x] implement Deref for this new type so it's easy to obtain the inner context pointer
- [x] add an unsafe from_ptr static method that returns a new instance of the type
- [x] start by changing various Argument uses in CodegenRust.py for python classes that inherit from CGAbstractMethod
- [x] convert the python code that interacts with CGClass (CGCallback, CGCallbackFunction, CGCallbackFunctionImpl, CGCallbackInterface) and any rust code that interacts with it
- [x] update CGDictionary and any rust code that interacts with it
- [x] make the code generator declare trait methods that accept the new type instead of *mut JSContext (CGInterfaceTrait)
- [x] modify GlobalScope::get_cx to return a SafeJSContext

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1 files changed, 8 insertions, 10 deletions

diff --git a/components/script/dom/permissions.rs b/components/script/dom/permissions.rs
index 5c6d7b0aed0..419115d1240 100644
--- a/components/script/dom/permissions.rs
+++ b/components/script/dom/permissions.rs
@@ -17,6 +17,7 @@ use crate::dom::bluetoothpermissionresult::BluetoothPermissionResult;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::permissionstatus::PermissionStatus;
 use crate::dom::promise::Promise;
+use crate::script_runtime::JSContext as SafeJSContext;
 use dom_struct::dom_struct;
 use js::conversions::ConversionResult;
 use js::jsapi::{JSContext, JSObject};
@@ -199,22 +200,19 @@ impl Permissions {
 }
 
 impl PermissionsMethods for Permissions {
-    #[allow(unsafe_code)]
     // https://w3c.github.io/permissions/#dom-permissions-query
-    unsafe fn Query(&self, cx: *mut JSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
-        self.manipulate(Operation::Query, cx, permissionDesc, None)
+    fn Query(&self, cx: SafeJSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
+        self.manipulate(Operation::Query, *cx, permissionDesc, None)
     }
 
-    #[allow(unsafe_code)]
     // https://w3c.github.io/permissions/#dom-permissions-request
-    unsafe fn Request(&self, cx: *mut JSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
-        self.manipulate(Operation::Request, cx, permissionDesc, None)
+    fn Request(&self, cx: SafeJSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
+        self.manipulate(Operation::Request, *cx, permissionDesc, None)
     }
 
-    #[allow(unsafe_code)]
     // https://w3c.github.io/permissions/#dom-permissions-revoke
-    unsafe fn Revoke(&self, cx: *mut JSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
-        self.manipulate(Operation::Revoke, cx, permissionDesc, None)
+    fn Revoke(&self, cx: SafeJSContext, permissionDesc: *mut JSObject) -> Rc<Promise> {
+        self.manipulate(Operation::Revoke, *cx, permissionDesc, None)
     }
 }
 
@@ -232,7 +230,7 @@ impl PermissionAlgorithm for Permissions {
             .handle_mut()
             .set(ObjectValue(permission_descriptor_obj));
         unsafe {
-            match PermissionDescriptor::new(cx, property.handle()) {
+            match PermissionDescriptor::new(SafeJSContext::from_ptr(cx), property.handle()) {
                 Ok(ConversionResult::Success(descriptor)) => Ok(descriptor),
                 Ok(ConversionResult::Failure(error)) => Err(Error::Type(error.into_owned())),
                 Err(_) => Err(Error::JSFailed),