Any RenderingContext/OffscreenRenderingContext type has readonly
"canvas" attribute
and associated native-code DOM context objects have reference to target
DOM canvas objects.
https://html.spec.whatwg.org/multipage/canvas.html#renderingcontexthttps://html.spec.whatwg.org/multipage/canvas.html#offscreenrenderingcontext
And currently the reference to DOM canvas object is the rooting pointer
on the stack,
which leads to the circular reference problem.
The SpiderMonkey's (SM) garbage collector will not be able to free the
DOM canvas and context
objects (unreacheble from JS) because of the rooting pointer on stack
(see STACK_ROOTS).
And these objects will be stored until the associated script
runtime/thread will be terminated.
SM -> JS Roots -> DOM Canvas* (on heap) -> DOM Context (on heap)
SM -> Rust Roots -> Dom Canvas* (on stack) <- as "canvas" member field
Let's replace the rooting pointer to the traceble pointer (DomRoot ->
Dom)
in the "canvas" member field of DOM context object, which allows to
broke circular referencing problem.
Testing: No changes in existed tests
Signed-off-by: Andrei Volykhin <volykhin.andrei@huawei.com>
Co-authored-by: Andrei Volykhin <volykhin.andrei@huawei.com>
