Bug 1639850 - adjust xpcshell on windows to remove frequent failures. r=gbrown

Differential Revision: https://phabricator.services.mozilla.com/D133119

docshell/test/unit/xpcshell.ini

@@ -16,7 +16,7 @@ skip-if = os == 'android'
 [test_URIFixup_info.js]
 skip-if =
   os == 'android'
-  win10_2004 && bits == 32 && debug  # Bug 1727925
+  win10_2004 && debug  # Bug 1727925
 [test_pb_notification.js]
 # Bug 751575: unrelated JS changes cause timeouts on random platforms
 skip-if = true

taskcluster/ci/test/xpcshell.yml

@@ -64,7 +64,7 @@ xpcshell:
             macosx.*-64(-shippable|-devedition|-asan)?(-qr)?/.*: 2
             linux1804-64(-qr)?/debug: 6
             .*-tsan-qr/opt: 8
-            windows.*(-shippable|-devedition|-asan|.*-qr)?/.*: 2
+            windows.*(-shippable|-devedition|-asan|.*-qr)?/.*: 4
             default: 5
     max-run-time:
         by-test-platform:
@@ -81,6 +81,12 @@ xpcshell:
                     windows10-64-2004-asan.*: 3
                     android-em-7.0-x86_64-qr/debug-isolated-process: 3
                     default: default
+    mozharness:
+        extra-options:
+            by-test-platform:
+                windows10.*:
+                    - --threads=2
+                default: []
     fetches:
         toolchain:
             by-test-platform:

testing/mozharness/scripts/desktop_unittest.py

@@ -218,6 +218,14 @@ class DesktopUnittest(TestingMixin, MercurialScript, MozbaseMixin, CodeCoverageM
                     "help": "Enable the WebRender compositor in Gecko.",
                 },
             ],
+            [
+                ["--threads"],
+                {
+                    "action": "store",
+                    "dest": "threads",
+                    "help": "Number of total chunks",
+                },
+            ],
             [
                 ["--gpu-required"],
                 {
@@ -611,6 +619,9 @@ class DesktopUnittest(TestingMixin, MercurialScript, MozbaseMixin, CodeCoverageM
             if c["enable_webrender"]:
                 base_cmd.append("--enable-webrender")
 
+            if c.get("threads"):
+                base_cmd.extend(["--threads", c["threads"]])
+
             if c["enable_xorigin_tests"]:
                 base_cmd.append("--enable-xorigin-tests")
 

toolkit/components/filewatcher/tests/xpcshell/xpcshell.ini

@@ -11,7 +11,7 @@ skip-if = os != "win"
 [test_watch_file_modification_single.js]
 [test_watch_directory_creation_single.js]
 [test_watch_directory_deletion_single.js]
-skip-if = win10_2004 && bits == 32 && debug # Bug 1727925
+skip-if = win10_2004 && debug # Bug 1727925
 [test_watch_many_changes.js]
 [test_watch_multi_paths.js]
 [test_watch_recursively.js]