REGRESSION(271265@main): Heap corruption crash while destructing WebG…

…LMultiDraw

https://bugs.webkit.org/show_bug.cgi?id=265538

Unreviewed crash fix for Windows port.
Windows port was crashing after 271265@main made WebGLExtension a
RefCounted subclass. Only WebGLMultiDraw has virtual destructor among
WebGLExtension subclasses. ~WebGLMultiDraw should be non-virtual as
well as other WebGLExtension subclasses.

* Source/WebCore/html/canvas/WebGLMultiDraw.h:
Removed virtual from ~WebGLMultiDraw.

Canonical link: https://commits.webkit.org/271315@main

Source/WebCore/html/canvas/WebGLMultiDraw.h

@@ -40,7 +40,7 @@ class WebGLMultiDraw final : public WebGLExtension<WebGLRenderingContextBase> {
     using Int32List = WebGLRenderingContextBase::TypedList<Int32Array, int32_t>;
 
     explicit WebGLMultiDraw(WebGLRenderingContextBase&);
-    virtual ~WebGLMultiDraw();
+    ~WebGLMultiDraw();
 
     static bool supported(GraphicsContextGL&);