[wptrunner] Add a wpewebkit_minibrowser product/browser.

This adds a new browser type to run tests with the WPE WebKit port.
It can be passed an optional `--headless` parameter to enable
headless testing with WPT. Otherwise wayland is required.

A pre-built nightly bundle can be also automatically downloaded and
installed by passing `--install-browser` to the WPT runner.
It shares with webkitgtk_minibrowser most of the logic to download
and install the built product.

Documentation is also added and the webkitgtk_minibrowser one updated
accordingly.

Unit tests are added and updated and also a small cleaning regarding
duplicated imports of shutil and shutil.which on tools/wpt/browser.py

docs/running-tests/from-local-system.md

@@ -173,6 +173,7 @@ here](command-line-arguments.html#run).
   android_webview
   safari
   webkitgtk_minibrowser
+  wpewebkit_minibrowser
 ```
 
 ### Running in parallel

docs/running-tests/webkitgtk_minibrowser.md

@@ -1,22 +1,71 @@
 # WebKitGTK MiniBrowser
 
+To be able to run tests with the [WebKitGTK](https://webkitgtk.org/)
+MiniBrowser you need the following packages installed:
 
-To be able to run tests with the WebKitGTK MiniBrowser you need the
-following packages installed:
-
-* Fedora: `webkit2gtk3-devel`
-* Debian or Ubuntu: `webkit2gtk-driver`
-
+* Fedora: `webkitgtk6.0`
+* Debian or Ubuntu: `webkitgtk-driver` or `webkit2gtk-driver`
+* Arch: `webkitgtk-6.0`
 
 The WebKitGTK MiniBrowser is not installed on the default binary path.
 The `wpt` script will try to automatically locate it, but if you need
 to run it manually you can find it on any of this paths:
 
-* Fedora: `/usr/libexec/webkit2gtk-${VERSION}/MiniBrowser`
-* Debian or Ubuntu: `/usr/lib/x86_64-linux-gnu/webkit2gtk-${VERSION}/MiniBrowser`
-* Note:
-     * `VERSION` is `4.0` or `4.1`.
-     * If not Fedora and the machine architecture is not `x86_64`, then it will
-      be located inside:
-      `/usr/lib/${TRIPLET}/webkit2gtk-${VERSION}/MiniBrowser`
-      where `TRIPLET=$(gcc -dumpmachine)`
+* Fedora: `/usr/libexec/webkitgtk-${APIVERSION}/MiniBrowser`
+* Arch: `/usr/lib/webkitgtk-${APIVERSION}/MiniBrowser`
+* Debian or Ubuntu: `/usr/lib/${TRIPLET}/webkitgtk-${APIVERSION}/MiniBrowser`
+  * Note: `${TRIPLET}` is the output of the command `gcc -dumpmachine`
+
+# Nightly universal bundle
+
+Alternatively you can pass to `wpt` the flags `--install-browser --channel=nightly`
+and then `wpt` will automatically download the last bundle and unpack it on the
+default `wpt` working directory (usually subdir `_venv3/browsers` in your `wpt` checkout)
+Then it will use the unpacked `MiniBrowser` and `WebKitWebDriver` binaries to run the tests.
+
+This universal bundles should work on any Linux distribution as they include inside
+the tarball all the system libraries and resources needed to run WebKitGTK, from libc
+up to the Mesa graphics drivers without requiring the usage of containers.
+
+If you are not using open source graphics drivers (Mesa) and you experiment issues
+with this bundles then a possible workaround is to try to run the tests headless
+inside a virtualized display like `Xvfb` (see command `xvfb-run -a` on Debian/Ubuntu).
+You can do this also from inside a virtual machine or docker container.
+
+# Headless mode
+
+WebKitGTK does not have a native headless mode, but you can workaround that
+by running the tests inside a virtualized display. For example you can use
+`weston` with the headless backend for a virtualized `Wayland` display,
+or you can use `Xvfb` for a virtualized `X11` display.
+
+Example:
+   ```
+   xvfb-run -a ./wpt run [more-options] webkitgtk_minibrowser [tests-to-run]
+   ```
+
+# Using a custom WebKitGTK build
+
+If you want to test with a custom WebKitGTK build the easiest way is that you
+install this build on a temporal directory and then tell wpt to run it from there.
+
+Steps:
+
+  1. Build WebKitGTK passing the arguments `-DENABLE_MINIBROWSER=ON -DCMAKE_INSTALL_PREFIX=/home/user/testdir_install`
+  2. Install it: `ninja install` (or `make install`)
+  3. Locate the `MiniBrowser` and `WebKitWebDriver` binaries under `/home/user/testdir_install`
+  4. Run `wpt` passing this two paths like this:
+  ```
+      ./wpt run --webdriver-binary=/home/user/testdir_install/bin/WebKitWebDriver \
+                --binary=/home/user/testdir_install/libexec/MiniBrowser \
+                [more-options] webkitgtk_minibrowser [tests-to-run]
+  ```
+
+ * Note: Is important that you build WebKitGTK against the libraries of your system.
+Do not build WebKitGTK inside Flatpak or other container unless you run `wpt` also
+from inside this container.
+
+# Running tests locally
+
+Is a good idea that you increase the verbosity of `wpt` by passing to it the flag `--log-mach=-`
+Also, please check the documentation about [Running Tests from the Local System](from-local-system).

docs/running-tests/wpewebkit_minibrowser.md

@@ -0,0 +1,67 @@
+# WPE WebKit MiniBrowser
+
+To be able to run tests with the [WPE WebKit](https://wpewebkit.org)
+MiniBrowser you need the following packages installed:
+
+* Fedora: N/A (build your own or use the nighly bundle)
+* Debian or Ubuntu: `wpewebkit-driver` and `libwpewebkit`
+* Arch:  `wpewebkit`
+
+The WPE WebKit MiniBrowser is not installed on the default binary path.
+The `wpt` script will try to automatically locate it, but if you need
+to run it manually you can find it on any of this paths:
+
+* Arch: `/usr/lib/wpe-webkit-${APIVERSION}/MiniBrowser`
+* Debian or Ubuntu: `/usr/lib/${TRIPLET}/wpe-webkit-${APIVERSION}/MiniBrowser`
+  * Note: `${TRIPLET}` is the output of the command `gcc -dumpmachine`
+
+# Nightly universal bundle
+
+Alternatively you can pass to `wpt` the flags `--install-browser --channel=nightly`
+and then `wpt` will automatically download the last bundle and unpack it on the
+default `wpt` working directory (usually subdir `_venv3/browsers` in your `wpt` checkout)
+Then it will use the unpacked `MiniBrowser` and `WPEWebDriver` binaries to run the tests.
+
+This universal bundles should work on any Linux distribution as they include inside
+the tarball all the system libraries and resources needed to run WebKitGTK, from libc
+up to the Mesa graphics drivers without requiring the usage of containers.
+
+If you are not using open source graphics drivers (Mesa) and you experiment issues
+with this bundles then a possible workaround is to try to run the tests in headless
+mode, for that pass the flag `--headless` to `wpt`
+
+# Headless mode
+
+The WPE MiniBrowser needs a Wayland display to run, but if you don't have one
+or you want to enable headless mode you can pass the flag `--headless` to `wpt`.
+
+Example:
+   ```
+   ./wpt run [more-options] --headless wpewebkit_minibrowser [tests-to-run]
+   ```
+
+# Using a custom WPE WebKit build
+
+If you want to test with a custom WPE WebKit build the easiest way is that you
+install this build on a temporal directory and then tell wpt to run it from there.
+
+Steps:
+
+  1. Build WPE WebKit passing the arguments `-DENABLE_MINIBROWSER=ON -DCMAKE_INSTALL_PREFIX=/home/user/testdir_install'
+  2. Install it: `ninja install` (or `make install`)
+  3. Locate the `MiniBrowser` and `WPEWebDriver` binaries under /home/user/testdir_install`
+  4. Run `wpt` passing this two paths like this:
+  ```
+      ./wpt run --webdriver-binary=/home/user/testdir_install/bin/WPEWebDriver \
+                --binary=/home/user/testdir_install/libexec/MiniBrowser \
+                [more-options] webkitgtk_minibrowser [tests-to-run]
+  ```
+
+Notes: Is important that you build WPE WebKit against the libraries of your system.
+Do not build WPE WebKit inside Flatpak or other container unless you run `wpt` also
+from inside this container.
+
+# Running tests locally
+
+Is a good idea that you increase the verbosity of `wpt` by passing to it the flag `--log-mach=-`
+Also, please check the documentation about [Running Tests from the Local System](from-local-system).