Make math dialog menu content scrollable

Also make input widget height respond to its contents. These two
changes address the problems of overlapping when the screen
height is limited.

Bug: T119900
Change-Id: Ie21c141673a9343d05da05cdbd2eaa96efff0a58

modules/ve-math/ve.ui.MWMathDialog.css

@@ -23,6 +23,7 @@
 .ve-ui-mwMathDialog-menuLayout > .oo-ui-menuLayout-content {
 	border-bottom: 1px solid #e6e6e6;
 	box-shadow: 0 1px 0 0 rgba( 0, 0, 0, 0.05 );
+	overflow: auto;
 }
 
 .ve-ui-mwMathPage-symbol {

modules/ve-math/ve.ui.MWMathDialog.js

@@ -101,7 +101,8 @@ ve.ui.MWMathDialog.prototype.initialize = function () {
 
 	this.input = new ve.ui.MWAceEditorWidget( {
 		multiline: true,
-		rows: 7,
+		autosize: true,
+		maxRows: 7,
 		autocomplete: 'live'
 	} ).setLanguage( 'latex' );