Tests: added njs extended logging tests.

js.t

diff --git a/js.t b/js.t
index 27aea6e..1e444d2 100644
--- a/js.t
+++ b/js.t
@@ -178,7 +178,9 @@
     }
 
     function test_log(req, res) {
-        req.log("SEE-THIS");
+        req.log("SEE-THIS-LOG");
+        req.warn("SEE-THIS-WARN");
+        req.error("SEE-THIS-ERROR");
     }
 
     function test_except(req, res) {
@@ -261,7 +263,7 @@
 
 EOF
 
-$t->try_run('no njs available')->plan(22);
+$t->try_run('no njs available')->plan(24);
 
 ###############################################################################
 
@@ -302,7 +304,9 @@
 
 $t->stop();
 
-ok(index($t->read_file('error.log'), 'SEE-THIS') > 0, 'log js');
+ok(index($t->read_file('error.log'), 'SEE-THIS-LOG') > 0, 'log js');
+ok(index($t->read_file('error.log'), 'SEE-THIS-WARN') > 0, 'warn js');
+ok(index($t->read_file('error.log'), 'SEE-THIS-ERROR') > 0, 'error js');
 ok(index($t->read_file('error.log'), 'at fs.readFileSync') > 0,
    'js_set backtrace');
 ok(index($t->read_file('error.log'), 'at JSON.parse') > 0,

stream_js.t

diff --git a/stream_js.t b/stream_js.t
index 1005ada..e251368 100644
--- a/stream_js.t
+++ b/stream_js.t
@@ -133,7 +133,9 @@
     }
 
     function js_log(sess) {
-        sess.log("SEE-THIS");
+        sess.log("SEE-THIS-LOG");
+        sess.warn("SEE-THIS-WARN");
+        sess.error("SEE-THIS-ERROR");
     }
 
     function js_access_allow(sess) {
@@ -199,7 +201,7 @@
 EOF
 
 $t->run_daemon(\&stream_daemon, port(8090));
-$t->try_run('no stream njs available')->plan(14);
+$t->try_run('no stream njs available')->plan(16);
 $t->waitforsocket('127.0.0.1:' . port(8090));
 
 ###############################################################################
@@ -223,7 +225,9 @@
 
 $t->stop();
 
-ok(index($t->read_file('error.log'), 'SEE-THIS') > 0, 'stream js log');
+ok(index($t->read_file('error.log'), 'SEE-THIS-LOG') > 0, 'stream js log');
+ok(index($t->read_file('error.log'), 'SEE-THIS-WARN') > 0, 'stream js warn');
+ok(index($t->read_file('error.log'), 'SEE-THIS-ERROR') > 0, 'stream js error');
 ok(index($t->read_file('error.log'), 'at fs.readFileSync') > 0,
    'stream js_preread backtrace');
 ok(index($t->read_file('error.log'), 'at js_filter_except') > 0,