Implementing activation behavior for <label>
Attempt to resolve#8179
@Manishearth , could you give me some resources having more information about what each function in `Activatable` does? The code compiles on my machine but I guess a lot more is needed
<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/8260)
<!-- Reviewable:end -->
Made binary files show an info message instead of garbled text.
Content-types with the TopLevel "Application" such as
* application/octet-stream
* application/pdf
now show an info message instead of trying to view binary data as html.
<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/7956)
<!-- Reviewable:end -->
Snap fragment scroll points to pixel boundaries
These don't match hardware pixels, but work well enough when the device
pixel ratio is a whole number.
<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/8276)
<!-- Reviewable:end -->
unblock using JS_GC_ZEAL
I think these patches move the `JS_SetReservedSlot` call to the right place for #6057. I'm not sure that the interface to `create_dom_global` is the best; passing a `JSVal` or a `*libc::c_void` seemed about equal, so I'd welcome feedback there.
<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/8226)
<!-- Reviewable:end -->
Moving this slot setting prior to initializing standard classes and
other initialization tasks means that we can effectively use JS_GC_ZEAL.
Fixes#6057.
We're going to wind up tacking on different pieces of code for the
global vs. non-global case once we move the JS_SetReservedSlot call into
create_dom_global. We might as well separate the indentation changes
into a separate commit.
This adds some overhead, but also provides the small performance benefit of
avoiding dirtying in the case where an event state is toggled an even
number of times between reflows.
The main benefit here though is that it sets us up to be smarter about
what we mark as dirty using restyle hints.
generate JIT argument type information for methods
This enhances `CodegenRust.py` to output `JSTypedMethodJitInfo` structures where appropriate. This brings a notable speedup to tests like Dromaeo's `dom-attr/getAttribute`, which improves by several orders of magnitude with these patches applied.
If there are tricks for addressing the XXX comments, I would appreciate hearing them.
I think this addresses all of #6904.
<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/8040)
<!-- Reviewable:end -->