[Origin Trials] Add tests for static methods on partial interfaces

third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js

Index: third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js b/third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js
index 623d5cc16e8e9c12b12d1076cba8229f0ef5cf3c..e1573e5236d8834e1f676cfc9ae12db39fecd336 100644
--- a/third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js
+++ b/third_party/WebKit/LayoutTests/http/tests/origin_trials/resources/origin_trials.js
@@ -50,6 +50,14 @@ expect_failure = (t) => {
         assert_not_exists(window.internals, 'frobulateMethodPartial');
         assert_equals(window.internals['frobulateMethodPartial'], undefined);
       }
+  }, {
+    desc: 'Static method should not exist on partial interface, with trial disabled',
+    code: () => {
+        var internalsInterface = window.internals.constructor;
+        assert_false('frobulateStaticMethodPartial' in internalsInterface);
+        assert_not_exists(internalsInterface, 'frobulateStaticMethodPartial');
+        assert_equals(internalsInterface['frobulateStaticMethodPartial'], undefined);
+      }
   }];
 
   fetch_tests_from_worker(new Worker('resources/disabled-worker.js'));
@@ -107,5 +115,11 @@ test(() => {
     assert_true(internalsInterface.frobulateStatic, 'Static attribute should return boolean value');
   }, 'Static attribute should exist on partial interface and return value');
 
+test(() => {
+    var internalsInterface = window.internals.constructor;
+    assert_exists(internalsInterface, 'frobulateStaticMethodPartial');
+    assert_true(internalsInterface.frobulateStaticMethodPartial(), 'Static method should return boolean value');
+  }, 'Static method should exist on partial interface and return value');
+
 fetch_tests_from_worker(new Worker('resources/enabled-worker.js'));
 };