Theme Installer: Left/right arrow keys in the overlay.

props adamsilverstein.
see #27521.

Built from https://develop.svn.wordpress.org/trunk@28036


git-svn-id: http://core.svn.wordpress.org/trunk@27866 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/theme.js

@@ -756,10 +756,19 @@ themes.view.Preview = themes.view.Details.extend({
 			$( 'body' )
 				.addClass( 'theme-installer-active full-overlay-active' )
 				.on( 'keyup.overlay', function( event ) {
-					// Pressing the escape key closes the preview
+					// The escape key closes the preview
 					if ( event.keyCode === 27 ) {
 						self.close();
 					}
+					// The right arrow key, next theme
+					if ( event.keyCode === 39 ) {
+						self.nextTheme();
+					}
+
+					// The left arrow key, previous theme
+					if ( event.keyCode === 37 ) {
+						self.previousTheme();
+					}
 				});
 			$( '.close-full-overlay' ).focus();
 		});