Implement Gradle flavors for Android VR compilations
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This PR adds support to easily generate Android VR builds. Rust/Java VR dependencies are not added by default.
Default build (No VR support)
```
./mach build --release --android
./mach package --release --android
./mach install --release --android
```
GoogleVR builds (e.g. Daydream)
```
./mach build --release --android --features googlevr
./mach package --release --android --flavor googlevr
./mach install --release --android
```
OculusVR builds (e.g. Gear VR)
```
./mach build --release --android --features oculusvr
./mach package --release --android --flavor oculusvr
./mach install --release --android
```
---
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- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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- 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
Support for Android armv7 and aarch64 target triples
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Support for Android armv7 and aarch64 target triples in python build scripts (build + packaging)
`--android` build parameter works as always (arm-linux-androideabi still the default)
`./mach build --release --android`
New compilation modes for android
`./mach build --release --target=arm-linux-androideabi`
`./mach build --release --target=armv7-linux-androideabi`
`./mach build --release --target=aarch64-linux-android`
See https://github.com/servo/servo/issues/11921. When all crates are ready we'll switch default android compilations to` armv7-linux-androideabi` target triple.
---
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- [ ] These changes fix #__ (github issue number if applicable).
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Majority of build_gecko.rs is just the straightforward conversion from
regen.py. There are two differences that:
1. Side in whitelist is changed to mozilla::Side
2. std::atomic__My_base is added to opaque types for Windows
Currently fonts are using incorrect metrics and the app uses the console
subsystem. This patch adds aliases so that font metrics are found and
instructs the linker to use the windows subsystem.
Don’t include microsecons when reporting build times.
"0:03:40.817715" is harder to read and no more informative than "0:03:40"
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It's actually quite weird that I had to do this, but I got errors without it. I noted the `BIN_SUFFIX` existed elsewhere so it felt logical to use it here also.
