Editbutton for math

Move the code that creates the Editbutton for math from core,
where it is removed in Ib17aa47c7d647e1ed293541adbdd1aa77e25e59e.

Imported button image from:
ssh://gerrit.wikimedia.org:29418/mediawiki/core.git/skins/common/button_math.png

We don't need to vary the icon per language, because there is not a
single language that has a non default icon.

Bug: 60471
Change-Id: I3d126c1c252c27fa65ab8fb42ffab66a2d99cfa8

Math.hooks.php

@@ -269,4 +269,14 @@ class MathHooks {
 
 		return true;
 	}
+
+	/**
+	 *
+	 * @global type $wgOut
+	 * @param type $toolbar
+	 */
+	static function onEditPageBeforeEditToolbar( &$toolbar ) {
+		global $wgOut;
+		$wgOut->addModules( array( 'ext.math.editbutton.enabler' ) );
+	}
 }

Math.php

@@ -153,6 +153,7 @@ $wgHooks['LoadExtensionSchemaUpdates'][] = 'MathHooks::onLoadExtensionSchemaUpda
 $wgHooks['ParserTestTables'][] = 'MathHooks::onParserTestTables';
 $wgHooks['UnitTestsList'][] = 'MathHooks::onRegisterUnitTests';
 $wgHooks['PageRenderingHash'][] = 'MathHooks::onPageRenderingHash';
+$wgHooks['EditPageBeforeEditToolbar'][] = 'MathHooks::onEditPageBeforeEditToolbar';
 
 $dir = __DIR__ . '/';
 $wgAutoloadClasses['MathHooks'] = $dir . 'Math.hooks.php';
@@ -403,6 +404,14 @@ $moduleTemplate = array(
     'remoteExtPath' => 'Math/modules',
 );
 
+$wgResourceModules['ext.math.editbutton.enabler'] = array(
+	'scripts' => 'ext.math.editbutton.js',
+	'messages' => array(
+		'math_tip',
+		'math_sample',
+	),
+) + $moduleTemplate;
+
 $wgResourceModules['ext.math.visualEditor'] = array(
 	'scripts' => array(
 		'VisualEditor/ve.dm.MWMathNode.js',

modules/ext.math.editbutton.js

@@ -0,0 +1,13 @@
+( function ( mw ) {
+	if ( mw.toolbar ) {
+		var iconPath = mw.config.get( 'wgExtensionAssetsPath' ) + '/Math/images/';
+		mw.toolbar.addButton( {
+			imageFile: iconPath + 'button_math.png',
+			speedTip: mw.msg( 'math_tip' ),
+			tagOpen: '<math>',
+			tagClose: '</math>',
+			sampleText: mw.msg( 'math_sample' ),
+			imageId: 'mw-editbutton-math'
+		} );
+	}
+} ( mediaWiki ) );