This implements the `canvas`, `drawingBufferHeight` and
`drawingBufferWidth` getters to `WebGLRenderingContext`, and an initial
version of `getParameter`.
r? @jdm
I couldn't add the `getContextAttributes` method since `CodegenRust`
doesn't know how to return a dictionary value, I'll take a look at it ASAP.
I think the helper functions can return directly the renderer, since they're used just for that, but I wanted to hear your opinions about this.
By the way I'm interested in adding more serious tests for WebGL, and I think the [khronos conformance suit](https://github.com/KhronosGroup/WebGL/tree/master/conformance-suites/1.0.3) should be the best option.
Should I try to integrate it in wpt, or making a `tests/webgl` directory (or similar) inside the servo tree? (Maybe this question should be for @Ms2ger)
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Known issues:
* Collapsed borders do not correctly affect the border-box of the table
itself.
* The content widths of all cells in a column and the content height of
all cells in a row is the same in this patch, but not in Gecko and
WebKit.
* Corners are not painted well. The spec does not say what to do here.
* Column spans are not handled well. The spec does not say what to do
here either.
wrapping on newlines rather than searching for a newline character.
Since the newline character might have been stripped out during
whitespace stripping, this was incorrect.
Fixes the "jumpiness" seen on the Google home page, Wikipedia, and many
other places.
Transition events are not yet supported, and the only animatable
properties are `top`, `right`, `bottom`, and `left`. However, all other
features of transitions are supported. There are no automated tests at
present because I'm not sure how best to test it, but three manual tests
are included.
What can this do? Reset `<input type=text>` fields back to their default
value through a call to a form's reset method. That's all for now!
Fixes compile error after rebase
