Fix Android build errors on macOS.
- Add sysroot path to environment variable 'CPPFLAGS':
When checking C preprocessor, the 'configure' script of libbacktrace uses 'CPPFLAGS' rather than 'CFLAGS' and doesn't get the correct search path. (#15758)
This check passes on Linux because the '/lib/cpp' fallback is available there.
- Introduce CMake toolchain file for Android cross compiling:
CMake needs several variables [1] to cross compile for Android.
It works (accidentally) on Linux because cmake-rs sets compilers correctly and binutils for Linux & Android are pretty much the same.
[1] https://cmake.org/cmake/help/v3.7/manual/cmake-toolchains.7.html#cross-compiling-for-android-with-the-ndk
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Preserve sourceURL comment on style sheets
In addition to the sourceMappingURL comment, there is a second special
comment, "sourceURL", that can be used to set the "display name" of a
style sheet for developer tools. This name is also used as the base
URL for the source-map URL resolution algorithm. sourceURL is
described here:
https://blog.getfirebug.com/2009/08/11/give-your-eval-a-name-with-sourceurl/
The devtools feature bug is here:
https://bugzilla.mozilla.org/show_bug.cgi?id=880831
This patch changes servo to preserve and expose this value for use in M-C.
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- [ ] These changes fix #__ (github issue number if applicable).
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style: Implement the body text color quirk in a more straight-forward way.
This avoids grabbing the body when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
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Do some minor cleanups in display list building
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Share specified URLs with Gecko
This makes use of our Arc offset machinery to allow Gecko to store Arc<String> values and ensure there are used appropriately.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix [bug 1397971](https://bugzilla.mozilla.org/show_bug.cgi?id=1397971).
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This avoids grabbing the document when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
