Move websocket creation to resource task
This is a pull request for part of https://github.com/servo/servo/issues/6638
It includes the following changes:
-The websocket networking code (ie. making a connection, receiving data, and sending data) has been extracted out of components/script/dom/websocket.rs and into the new file components/net/websocket_loader.rs.
-websocket.rs now communicates with the resource task (components/net/resource_task.rs) to instruct it to initiate a new websocket connection
- websocket_loader.rs now provides an API sent over an IPCChannel that allows websocket.rs to receive feedback about this process and to subsequently send and receive data
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Fix redraw of WPT UI output, and slightly improve line counting
See discussion in PR #8551.
Redraw of the first test name was broken due to a mix-up between two ANSI escape codes.
I also took the opportunity to change the way line count is calculated. It's a bit cleaner that way (the new operation is ~%20 faster, but that's unnoticeable).
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M1504: Implement basic support for withCredentials API
The pull request includes the following task:
* Implemented basic network-level support by adding a member to LoadData that is used by http_loader.rs to conditionally exclude cookies from the HTTP request if the flag is false (default true)
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M1503 : Integrate XML Parser : First 2 of 4 Subsequent Steps
Rebase of #8746. Introduce and use an XML parser for text/xml network responses when loading web pages.
webgl: Fix texturing
These two tiny changes were making WebGL textures not work.
It was not seen in our texturing test since it only used one texture,
we render to a texture by default, and that texture was bound to
`gl::TEXTURE_2D`.
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fix intermittent Option::unwrap in timers
fixes intermittent #8616
This intermittent indicates real problem in code.
Lets consider such code:
```javascript
// timer 1
setTimeout(function() {
//timer 2
setTimeout(function() {}, 0);
}, 0);
```
When we receive event to fire timer 1 it will be selected and extracted from active timers list in fire_timer function. During timer 1 handler execution we will schedule timer 2 and request timer event for it. But it will be executed during same fire_timer call because of 0 timeout. And as a result we will have empty timers list and expecting event for timer 2 that will crash in assert.
I'm not sure that all I've written is clear, but we have something like this:
```
install timer 1 -> [1] in timers list
push and expect timer event 1 -> expected_event=1
received timer event 1
fire_timer()
select timer 1 to execute -> [] in timers list
execute timer 1 handler
install timer 2 -> [2] in timers list
push and expect timer event 2 -> expected_event=2
select timer 2 to execute (because of 0 timeout) -> [] in tiemrs list
execute timer 2 handler
expected_event=2 is dangling
received timer event 2
fire_timer() -> BOOM
```
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The validations performed in the script side of this should always
prevent this from happening, and this will allow us to catch bugs like
the previous one.
