fold Apache error.log and ignored PHP syntax errors, plus remove some warnings

.travis.yml

@@ -72,9 +72,11 @@ script:
   # Ubuntu has problems with #!/usr/bin/env php -dapc.enable=1, it stalls forever
   - vendor/bin/phpunit -c doc -dapc.enable_cli=1
   # output Apache error.log to diagnose PHP errors in requests send by unit-tests
+  - echo "travis_fold:start:SCRIPT folding starts"
   - sudo cat /var/log/apache2/error.log
   # do not run syntax check for hhvm, as it always fails / get terminated after 10m
-  - test $(phpenv version-name) = 'hhvm' || ./doc/php_syntax_check.sh
+  - ./doc/php_syntax_check.sh
+  - echo "travis_fold:start:SCRIPT folding ends"
 
 cache:
   directories:

api/src/Session.php

@@ -1976,6 +1976,7 @@ class Session
 			case PHP_SESSION_DISABLED:
 				throw new \ErrorException('EGroupware requires PHP session extension!');
 			case PHP_SESSION_NONE:
+				if (headers_sent()) return false;	// only gives warnings
 				ini_set('session.use_cookies',0);	// disable the automatic use of cookies, as it uses the path / by default
 				session_name(self::EGW_SESSION_NAME);
 				if (($sessionid = self::get_sessionid()))

api/src/Vfs/Sharing.php

@@ -90,9 +90,8 @@ class Sharing extends \EGroupware\Api\Sharing
 	 */
 	public static function setup_share($keep_session, &$share)
 	{
-
 		// need to reset fs_tab, as resolve_url does NOT work with just share mounted
-		if (count($GLOBALS['egw_info']['server']['vfs_fstab']) <= 1)
+		if (empty($GLOBALS['egw_info']['server']['vfs_fstab']) || count($GLOBALS['egw_info']['server']['vfs_fstab']) <= 1)
 		{
 			unset($GLOBALS['egw_info']['server']['vfs_fstab']);	// triggers reset of fstab in mount()
 			$GLOBALS['egw_info']['server']['vfs_fstab'] = Vfs::mount();