Auto merge of #21158 - ferjm:webaudio, r=manishearth,nox,ferjm

WebAudio API

- [X] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #6710
- [X] There are tests for these changes

This PR adds basic support for the WebAudio API using [servo-media](https://github.com/servo/media) with GStreamer as the audio backend.

There are still some major stuff to fix like:

- [x] Detach ArrayBuffer during the [AudioBuffer "acquire the content" operation](https://webaudio.github.io/web-audio-api/#acquire-the-content). I am naively using `JS_StealArrayBufferContents()` directly, because it is what Gecko uses, but this should probably be part of the [rust-mozjs](https://github.com/servo/rust-mozjs) [TypedArray](https://github.com/servo/rust-mozjs/blob/master/src/typedarray.rs) API. And, in any case, I am not even sure if that's the proper way to do it. According to the results of the WPTs it may not even be right since [this assertion](https://github.com/servo/rust-mozjs/blob/master/src/typedarray.rs#L285) is failing in some cases. I need to dig more about this.
- [x] Disable the GStreamer dependency on Android. Unfortunately gstreamer-rs requires an NDK version upgrade, so we need to disable this for Android until then. I tried adding [different features to servo-media](servo/media#79), but I am currently hitting [this issue](rust-lang/cargo#1197)

I still need to run servo-tidy, change the servo-media dependency to use the git repo and add/fix some comments and TODOs.

The remaining feature work should be done in future PRs.

Note that most of the failing WPTs are failing because we don't implement the tested features yet (we only implement a few AudioNodes) and we have no OfflineAudioContext support, which most WPTs rely on.

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.travis.yml

@@ -17,6 +17,13 @@ matrix:
         - sudo add-apt-repository 'deb http://apt.llvm.org/precise/ llvm-toolchain-precise-3.9 main' -y
         - sudo apt-get update -q
         - sudo apt-get install clang-3.9 llvm-3.9 llvm-3.9-runtime -y
+        - curl -L https://github.com/ferjm/gstreamer-1.14.1-ubuntu-trusty/raw/master/gstreamer.tar.gz | tar xz
+        - sed -i "s;prefix=/root/gstreamer;prefix=$PWD/gstreamer;g" $PWD/gstreamer/lib/x86_64-linux-gnu/pkgconfig/*.pc
+        - export PKG_CONFIG_PATH=$PWD/gstreamer/lib/x86_64-linux-gnu/pkgconfig
+        - export GST_PLUGIN_SYSTEM_PATH=$PWD/gstreamer/lib/x86_64-linux-gnu/gstreamer-1.0
+        - export GST_PLUGIN_SCANNER=$PWD/gstreamer/libexec/gstreamer-1.0/gst-plugin-scanner
+        - export PATH=$PATH:$PWD/gstreamer/bin
+        - export LD_LIBRARY_PATH=$PWD/gstreamer/lib/x86_64-linux-gnu:$LD_LIBRARY_PATH
         - export LLVM_CONFIG=/usr/lib/llvm-3.9/bin/llvm-config
         - curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none -y
         - source ~/.profile
@@ -52,6 +59,7 @@ matrix:
             - ccache
             - libdbus-glib-1-dev
             - libedit-dev
+            - libglib2.0-dev
 
 branches:
   only:

README.md

@@ -83,7 +83,8 @@ sudo apt install git curl autoconf libx11-dev \
     gperf g++ build-essential cmake virtualenv python-pip \
     libssl1.0-dev libbz2-dev libosmesa6-dev libxmu6 libxmu-dev \
     libglu1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libdbus-1-dev \
-    libharfbuzz-dev ccache clang
+    libharfbuzz-dev ccache clang \
+    libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev
 ```
 
 If you using a version prior to **Ubuntu 17.04** or **Debian Sid**, replace `libssl1.0-dev` with `libssl-dev`.

appveyor.yml

@@ -43,9 +43,17 @@ cache:
   - .ccache
 
 install:
+  - choco install pkgconfiglite
+  - appveyor-retry appveyor DownloadFile https://gstreamer.freedesktop.org/data/pkg/windows/1.14.1/gstreamer-1.0-devel-x86_64-1.14.1.msi
+  - appveyor-retry appveyor DownloadFile https://gstreamer.freedesktop.org/data/pkg/windows/1.14.1/gstreamer-1.0-x86_64-1.14.1.msi
+  - msiexec /i gstreamer-1.0-devel-x86_64-1.14.1.msi /quiet /qn /norestart /log install-devel.log
+  - msiexec /i gstreamer-1.0-x86_64-1.14.1.msi /quiet /qn /norestart /log install.log
   - appveyor-retry appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
   - rustup-init.exe -y --default-host x86_64-pc-windows-msvc --default-toolchain none
   - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
+  - set PKG_CONFIG_PATH=%PKG_CONFIG_PATH%;C:\gstreamer\1.0\x86_64\lib\pkgconfig
+  - set LIB=C:\gstreamer\1.0\x86_64\lib
+  - set LIBPATH=C:\gstreamer\1.0\x86_64\lib
   - rustup -V
   - mach rustc --version
   - mach cargo --version

components/atoms/static_atoms.txt

@@ -12,13 +12,15 @@ checkbox
 click
 close
 color
+complete
 controllerchange
 cursive
 date
 datetime-local
 dir
 email
 emptied
+ended
 error
 fantasy
 fetch

components/fallible/Cargo.toml

@@ -10,7 +10,7 @@ name = "fallible"
 path = "lib.rs"
 
 [dependencies]
-smallvec = "0.6"
+smallvec = "0.6.2"
 hashglobe = { path = "../hashglobe" }
 
 # This crate effectively does nothing except if the `known_system_malloc`

components/gfx/Cargo.toml

@@ -36,7 +36,7 @@ serde = "1.0"
 servo_arc = {path = "../servo_arc"}
 servo_atoms = {path = "../atoms"}
 servo_url = {path = "../url"}
-smallvec = "0.6"
+smallvec = "0.6.2"
 style = {path = "../style"}
 time = "0.1.12"
 unicode-bidi = {version = "0.3", features = ["with_serde"]}

components/layout/Cargo.toml

@@ -42,7 +42,7 @@ servo_geometry = {path = "../geometry"}
 serde_json = "1.0"
 servo_config = {path = "../config"}
 servo_url = {path = "../url"}
-smallvec = "0.6"
+smallvec = "0.6.2"
 style = {path = "../style", features = ["servo"]}
 style_traits = {path = "../style_traits"}
 unicode-bidi = {version = "0.3", features = ["with_serde"]}

components/script/Cargo.toml

@@ -87,9 +87,10 @@ servo_arc = {path = "../servo_arc"}
 servo_atoms = {path = "../atoms"}
 servo_config = {path = "../config"}
 servo_geometry = {path = "../geometry" }
+servo-media = {git = "https://github.com/servo/media"}
 servo_rand = {path = "../rand"}
 servo_url = {path = "../url"}
-smallvec = "0.6"
+smallvec = "0.6.2"
 style = {path = "../style", features = ["servo"]}
 style_traits = {path = "../style_traits"}
 swapper = "0.1"