Simplify ResourceLoaderULSModule with content-based versioning

* Remove manual tracking of when a hash is first seen.
  ResourceLoader is no longer time-based, rather it is content based.
  Except where a timestamp is actually wanted as key, a hash is all
  we need. The default implementation of simply calling getScript()
  and hashing its output suffices, and isn't a performance problem
  in this case.

* Also simplify getScript() by passing an object to 'mw.config.set'.
  Instead of multiple calls for each key/value. This is a no-op
  now because there is only one key.

* Fix inaccurate class comment that was copied from an unrelated
  module in MediaWiki core.

Change-Id: I9bb82cadd9caa7e584e20dd49ce30b64218326c4

tests/phpunit/ResourceLoaderULSTest.php

@@ -1,49 +0,0 @@
-<?php
-/**
- * PHP Unit tests for ResourceLoaderULSModule class.
- *
- * @file
- * @ingroup Extensions
- *
- * @author Santhosh Thottingal
- */
-
-/**
- * @covers ResourceLoaderULSModule
- */
-class ResourceLoaderULSModuleMemcachedTest extends MediaWikiTestCase {
-	/**
-	 * Test whether the modified time of the RL module varies
-	 * correctly with language code.
-	 * @covers ResourceLoaderSchemaModule::getModifiedTime
-	 */
-	public function testModifiedTime() {
-		$request = new WebRequest();
-		$module = new ResourceLoaderULSModule();
-
-		$request->setVal( 'lang', 'he' );
-		$context = new ResourceLoaderContext(
-			new ResourceLoader(), $request );
-		$mtimeHebrew = $module->getModifiedTime( $context );
-		// sleep for 1 second
-		sleep( 1 );
-		$request->setVal( 'lang', 'hi' );
-		$context = new ResourceLoaderContext( new ResourceLoader(), $request );
-		$mtimeHindi = $module->getModifiedTime( $context );
-		$this->assertGreaterThan( $mtimeHebrew, $mtimeHindi, 'Hindi has recent timestamp than Hebrew' );
-
-		// sleep for 1 second
-		sleep( 1 );
-		$request->setVal( 'lang', 'he' );
-		$context = new ResourceLoaderContext( new ResourceLoader(), $request );
-		$mtimeHebrewNew = $module->getModifiedTime( $context );
-		$this->assertEquals( $mtimeHebrewNew, $mtimeHebrew, 'Hebrew timestamp remained same' );
-
-		// sleep for 1 second
-		sleep( 1 );
-		$request->setVal( 'lang', 'hi' );
-		$context = new ResourceLoaderContext( new ResourceLoader(), $request );
-		$mtimeHindiNew = $module->getModifiedTime( $context );
-		$this->assertEquals( $mtimeHindi, $mtimeHindiNew, 'Hindi timestamp remained same' );
-	}
-}