[IMP] web: force mobile screen size for mobile suite

Before this rev., the mobile js tests suite was run on a desktop
like chrome-headless (1366x768). This can be a problem for this
suite which tests mobile behaviors and thus clicks on parts of the
interface that are only visible on small devices (thanks to scss
media queries).

This wasn't really a problem until now, because the test framework
allowed to click on invisible elements. But it's no longer the
case since the introduction of click helpers.

addons/web/tests/test_js.py

@@ -10,14 +10,10 @@ RE_ONLY = re.compile('QUnit\.only\(')
 @odoo.tests.tagged('post_install', '-at_install')
 class WebSuite(odoo.tests.HttpCase):
 
-    def test_01_js(self):
+    def test_js(self):
         # webclient desktop test suite
         self.phantom_js('/web/tests?mod=web&failfast', "", "", login='admin', timeout=1800)
 
-    def test_02_js(self):
-        # webclient mobile test suite
-        self.phantom_js('/web/tests/mobile?mod=web&failfast', "", "", login='admin', timeout=1800)
-
     def test_check_suite(self):
         # verify no js test is using `QUnit.only` as it forbid any other test to be executed
         self._check_only_call('web.qunit_suite')
@@ -35,3 +31,12 @@ class WebSuite(odoo.tests.HttpCase):
             with open(filename, 'rb') as fp:
                 if RE_ONLY.search(fp.read().decode('utf-8')):
                     self.fail("`QUnit.only()` used in file %r" % asset['url'])
+
+
+@odoo.tests.tagged('post_install', '-at_install')
+class MobileWebSuite(odoo.tests.HttpCase):
+    browser_size = '375x667'
+
+    def test_mobile_js(self):
+        # webclient mobile test suite
+        self.phantom_js('/web/tests/mobile?mod=web&failfast', "", "", login='admin', timeout=1800)