Fix php 7.2

htdocs/core/lib/json.lib.php

@@ -49,12 +49,15 @@ function dol_json_encode($elements)
 {
 	dol_syslog('dol_json_encode() is deprecated. Please update your code to use native json_encode().', LOG_WARNING);
 
-	$num=count($elements);
+	$num=0;
 	if (is_object($elements))	// Count number of properties for an object
 	{
-		$num=0;
 		foreach($elements as $key => $value) $num++;
 	}
+	else
+	{
+	    $num=count($elements);
+	}
 	//var_dump($num);
 
 	// determine type

test/phpunit/JsonLibTest.php

@@ -167,7 +167,5 @@ class JsonLibTest extends PHPUnit_Framework_TestCase
         $objecttotest->property3=$now;
         $encoded=dol_json_encode($objecttotest);
         $this->assertEquals('{"property1":"abc","property2":1234,"property3":43200}',$encoded);
-
     }
-
 }