Fix fnSetFilteringDelay when filtering disabled

Adds a check to fnSetFilteringDelay() that the table actually has the search box enabled - previously calling fnSetFilteringDelay() for a table without filtering would hijack ALL the search input box 'keyup' bindings on the whole page.

api/fnSetFilteringDelay.js

@@ -29,25 +29,28 @@ jQuery.fn.dataTableExt.oApi.fnSetFilteringDelay = function ( oSettings, iDelay )
 	}
 
 	this.each( function ( i ) {
-		$.fn.dataTableExt.iApiIndex = i;
-		var
-			oTimerId = null,
-			sPreviousSearch = null,
-			anControl = $( 'input', _that.fnSettings().aanFeatures.f );
+        	if ( typeof _that.fnSettings().aanFeatures.f !== 'undefined' )
+        	{
+			$.fn.dataTableExt.iApiIndex = i;
+			var
+				oTimerId = null,
+				sPreviousSearch = null,
+				anControl = $( 'input', _that.fnSettings().aanFeatures.f );
 	
-		anControl.unbind( 'keyup search input' ).bind( 'keyup search input', function() {
+			anControl.unbind( 'keyup search input' ).bind( 'keyup search input', function() {
 	
-			if (sPreviousSearch === null || sPreviousSearch != anControl.val()) {
-				window.clearTimeout(oTimerId);
-				sPreviousSearch = anControl.val();
-				oTimerId = window.setTimeout(function() {
-					$.fn.dataTableExt.iApiIndex = i;
-					_that.fnFilter( anControl.val() );
-				}, iDelay);
-			}
-		});
+				if (sPreviousSearch === null || sPreviousSearch != anControl.val()) {
+					window.clearTimeout(oTimerId);
+					sPreviousSearch = anControl.val();
+					oTimerId = window.setTimeout(function() {
+						$.fn.dataTableExt.iApiIndex = i;
+						_that.fnFilter( anControl.val() );
+					}, iDelay);
+				}
+			});
 	
-		return this;
+			return this;
+        	}
 	} );
 	return this;
 };