Allow skins/extensions to define custom OOUI themes

This change follows I39cc2a735d9625c87bf4ede6f5fb0ec441d47dcc.

docs/extension.schema.v1.json
docs/extension.schema.v2.json
includes/registration/ExtensionProcessor.php
* The new extension attribute 'OOUIThemePaths' can be used to define
  custom OOUI themes. See I9187a63e509b601b8558ea82850fa828e5c8cc0a
  for an example usage.

includes/resourceloader/ResourceLoaderOOUIModule.php
* Add support for 'OOUIThemePaths'.
* Defining 'images' is now optional. I figure custom themes are
  unlikely to have or need them.
* Use ResourceLoaderFilePath objects to allow skin-/extension-defined
  OOUI module files to use skin/extension's base paths.
  This was previously used to support $wgResourceModuleSkinStyles,
  but only for 'skinStyles' - now ResourceLoaderFileModule needs
  to also handle it for 'skinScripts', and ResourceLoaderImageModule
  for 'images').

includes/resourceloader/ResourceLoaderFilePath.php
* Add getters for local/remote base paths, for when we need to
  construct a new ResourceLoaderFilePath based on existing one.

includes/resourceloader/ResourceLoaderFileModule.php
includes/resourceloader/ResourceLoaderImageModule.php
includes/resourceloader/ResourceLoaderOOUIImageModule.php
* Add or improve handling of ResourceLoaderFilePaths:
  * Replace `(array)` casts with explicit array wrapping, to avoid
    casting objects into associative arrays.
  * Use getLocalPath() instead of string concatenation.

tests/phpunit/includes/resourceloader/ResourceLoaderFileModuleTest.php
tests/phpunit/includes/resourceloader/ResourceLoaderImageModuleTest.php
* Some basic checks for the above.

Bug: T100896
Change-Id: I74362f0fc215b26f1f104ce7bdbbac1e106736ad

7 files changed, 11 insertions, 0 deletions

diff --git a/tests/phpunit/data/rlfilepath/eye.svg b/tests/phpunit/data/rlfilepath/eye.svg
new file mode 100644
index 000000000000..be0c4e69d0e8
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/eye.svg
@@ -0,0 +1 @@
+<?xml version="1.0" encoding="UTF-8"?><svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20"><title>eye</title><path d="M10 7.5a2.5 2.5 0 1 0 2.5 2.5A2.5 2.5 0 0 0 10 7.5zm0 7a4.5 4.5 0 1 1 4.5-4.5 4.5 4.5 0 0 1-4.5 4.5zM10 3C3 3 0 10 0 10s3 7 10 7 10-7 10-7-3-7-10-7z"/></svg>
\ No newline at end of file
diff --git a/tests/phpunit/data/rlfilepath/flag-ltr.svg b/tests/phpunit/data/rlfilepath/flag-ltr.svg
new file mode 100644
index 000000000000..d19bed5371e3
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/flag-ltr.svg
@@ -0,0 +1 @@
+<?xml version="1.0" encoding="UTF-8"?><svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20"><title>flag</title><path d="M17 6L3 1v18h2v-6.87L17 6z"/></svg>
\ No newline at end of file
diff --git a/tests/phpunit/data/rlfilepath/flag-rtl.svg b/tests/phpunit/data/rlfilepath/flag-rtl.svg
new file mode 100644
index 000000000000..a58bb9242012
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/flag-rtl.svg
@@ -0,0 +1 @@
+<?xml version="1.0" encoding="UTF-8"?><svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20"><title>flag</title><path d="M3 6l14-5v18h-2v-6.87L3 6z"/></svg>
\ No newline at end of file
diff --git a/tests/phpunit/data/rlfilepath/script.js b/tests/phpunit/data/rlfilepath/script.js
new file mode 100644
index 000000000000..f5d7aa52abdb
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/script.js
@@ -0,0 +1 @@
+mw.test();
diff --git a/tests/phpunit/data/rlfilepath/skinStyle.css b/tests/phpunit/data/rlfilepath/skinStyle.css
new file mode 100644
index 000000000000..575d19f7b0e2
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/skinStyle.css
@@ -0,0 +1,3 @@
+body {
+	color: red;
+}
diff --git a/tests/phpunit/data/rlfilepath/style.css b/tests/phpunit/data/rlfilepath/style.css
new file mode 100644
index 000000000000..e87cc6abcd07
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/style.css
@@ -0,0 +1,3 @@
+body {
+	color: black;
+}
diff --git a/tests/phpunit/data/rlfilepath/template.html b/tests/phpunit/data/rlfilepath/template.html
new file mode 100644
index 000000000000..7c89b545c5ac
--- /dev/null
+++ b/tests/phpunit/data/rlfilepath/template.html
@@ -0,0 +1 @@
+<div></div>