This is being done in some places, we could do it in more
Related to this:
There are a number of places in WebCore, but outside of the accessibility code, in which Document::existingAXObjectCache() is called without first checking AXObjectCache::accessibilityEnabled().
If the checks that are present (e.g. in RenderBlockLineLayout.cpp, RenderImage.cpp) are indeed worth doing, they are potentially also worth doing in RenderBlock.cpp and RenderWidget.cpp, and RenderText.cpp, and RenderMenuList.cpp, and ....
Or we could instead just add a single: