Bug 1647720 - Replace fission with fission-xorigin variant, for linux64 mochitest-plain only; r=ahal

Differential Revision: https://phabricator.services.mozilla.com/D84611

taskcluster/ci/config.yml

@@ -51,6 +51,7 @@ treeherder:
         'M': 'Mochitests'
         'M-1proc': 'Mochitests without e10s'
         'M-fis': 'Mochitests with fission enabled'
+        'M-fis-xorig': 'Mochitests with cross-origin and fission enabled'
         'M-gli': 'Mochitests with WebGL over IPC'
         'M-spi': 'Mochitests with socket process'
         'M-spi-1proc': 'Mochitests with socket process without e10s'

taskcluster/ci/test/mochitest.yml

@@ -54,6 +54,11 @@ mochitest-plain:
     schedules-component: mochitest-plain
     loopback-video: true
     tier: default
+    variants:
+        by-test-platform:
+            linux1804-64/opt: ['fission-xorigin']
+            linux1804-64/debug: ['fission-xorigin']
+            default: ['fission']
     chunks:
         by-test-platform:
             android-em-7.*: 4

taskcluster/taskgraph/transforms/tests.py

@@ -196,6 +196,24 @@ TEST_VARIANTS = {
             },
         },
     },
+    'fission-xorigin': {
+        'description': "{description} with cross-origin and fission enabled",
+        'filterfn': fission_filter,
+        'suffix': 'fis-xorig',
+        'replace': {
+            'e10s': True,
+        },
+        'merge': {
+            # Ensures the default state is to not run anywhere.
+            'fission-run-on-projects': [],
+            'mozharness': {
+                'extra-options': ['--setpref=fission.autostart=true',
+                                  '--setpref=dom.serviceWorkers.parent_intercept=true',
+                                  '--setpref=browser.tabs.documentchannel=true',
+                                  '--enable-xorigin-tests'],
+            },
+        },
+    },
     'socketprocess': {
         'description': "{description} with socket process enabled",
         'suffix': 'spi',
@@ -1344,7 +1362,8 @@ def handle_fission_attributes(config, tasks):
         for attr in ('run-on-projects', 'tier'):
             fission_attr = task.pop('fission-{}'.format(attr), None)
 
-            if task['attributes'].get('unittest_variant') != 'fission' or fission_attr is None:
+            if (task['attributes'].get('unittest_variant') != 'fission-xorigin' and
+                task['attributes'].get('unittest_variant') != 'fission') or fission_attr is None:
                 continue
 
             task[attr] = fission_attr

testing/mozharness/scripts/desktop_unittest.py

@@ -169,6 +169,12 @@ class DesktopUnittest(TestingMixin, MercurialScript, MozbaseMixin,
             "help": "Repeat the tests the given number of times. Supported "
                     "by mochitest, reftest, crashtest, ignored otherwise."}
          ],
+        [["--enable-xorigin-tests"], {
+            "action": "store_true",
+            "dest": "enable_xorigin_tests",
+            "default": False,
+            "help": "Run tests in a cross origin iframe."}
+         ],
     ] + copy.deepcopy(testing_config_options) + \
         copy.deepcopy(code_coverage_config_options)
 
@@ -434,6 +440,9 @@ class DesktopUnittest(TestingMixin, MercurialScript, MozbaseMixin,
             if c['enable_webrender']:
                 base_cmd.append('--enable-webrender')
 
+            if c['enable_xorigin_tests']:
+                base_cmd.append('--enable-xorigin-tests')
+
             if c['extra_prefs']:
                 base_cmd.extend(['--setpref={}'.format(p) for p in c['extra_prefs']])