Allow setting preferences to false in WPT tests
First patch to servo - apologies if I did something stupid :)
This is a fix for #10161. I have squashed the commits into one.
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Parallel display list construction hasn't been shown to give any
performance gains. It is also incompatible with the current flat display
list implementation. Once flat display lists have landed, we can explore
possible benefits of parallel construction once again.
WebRender is an experimental GPU accelerated rendering backend for Servo.
The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).
WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!
This implements #7158 by conditionally choosing a UA string by
`#[cfg()]`-checking for `target_os = linux` and whether `target_arch` is
`x86_64` or not. Matching the behavior of Firefox, either "X11; Linux
x86_64" or "X11; Linux i686" is included.
`target_os = windows` is also checked; again as in Firefox "Windows NT
6.1; Win64; x64" or just "Windows NT 6.1" is included. The UA string
pretends to be non-WoW64 Windows 7, since there's only so much we can
detect at build time.
The existing desktop UA string that lists OS X is chosen if `target_os`
is neither `linux` nor `windows`.
This is enabled by default on Android, because Glutin currently sends mouse
events instead of touch events on Android. It's also useful for testing on
non-touch platforms.
Add an option to dump the layer tree, which activates the previously
unused layer tree debugging code. Also improve the output using the
PrintTree struct.
This allows both boolean and string-type preferences. It
also implements a system where prefs that are read from a
configuration file can be reset back to their initial value,
which is useful in a number of cases e.g. when running tests
to ensure that each test starts with the same values for
the prefs.
Fix#7609, "error: unable to create file tests/ref/hello_a?foo#bar.html
(Invalid argument)" during git checkout on Windows.
Behavior change: passing an nonexistent file name on the command line
now shows a blank page (like network errors)
rather than exit with an error message.
`OptionalIpcSender<T>`.
`OptionalIpcSender<T>`dynamically switches between in-process and
out-of-process communication depending on whether multiprocess mode is
enabled.
The multiprocess command-line switch doesn't actually turn on
multiprocess mode yet, but it does control the behavior of
`OptionalIpcSender<T>`.
