Bug 1697053 - Let non-native-theme ride the trains in Firefox 89. r=cpeterson,mstange

Differential Revision: https://phabricator.services.mozilla.com/D109555

modules/libpref/init/StaticPrefList.yaml

@@ -10756,7 +10756,7 @@
 # entry in python/mozbuild/mozbuild/mozinfo.py and test_fission_autostart.py
 - name: widget.non-native-theme.enabled
   type: RelaxedAtomicBool
-  value: @IS_NIGHTLY_BUILD@
+  value: true
   mirror: always
 
 # The size in CSS pixels at full zoom of the minimum scrollbar width.

python/mozbuild/mozbuild/mozinfo.py

@@ -96,7 +96,7 @@ def build_dict(config, env=os.environ):
     d["artifact"] = substs.get("MOZ_ARTIFACT_BUILDS") == "1"
     d["ccov"] = substs.get("MOZ_CODE_COVERAGE") == "1"
     d["cc_type"] = substs.get("CC_TYPE")
-    d["non_native_theme"] = d["nightly_build"]
+    d["non_native_theme"] = True
 
     def guess_platform():
         if d["buildapp"] == "browser":

toolkit/xre/nsAppRunner.cpp

@@ -494,9 +494,6 @@ static const char kPrefFissionExperimentEnrollmentStatus[] =
 static const char kPrefFissionExperimentStartupEnrollmentStatus[] =
     "fission.experiment.startupEnrollmentStatus";
 
-static const char kPrefNonNativeThemeEnabled[] =
-    "widget.non-native-theme.enabled";
-
 // The computed FissionAutostart value for the session, read by content
 // processes to initialize gFissionAutostart.
 //
@@ -731,12 +728,6 @@ static void EnsureFissionAutostartInitialized() {
                        PrefValueKind::Default);
   Preferences::Lock(kPrefFissionAutostartSession);
 
-  if (gFissionExperimentStatus == nsIXULRuntime::eExperimentStatusControl ||
-      gFissionExperimentStatus == nsIXULRuntime::eExperimentStatusTreatment) {
-    Preferences::SetBool(kPrefNonNativeThemeEnabled, true,
-                         PrefValueKind::Default);
-  }
-
   // If we're actively enrolled in the fission experiment, disqualify the user
   // from the experiment if the fission pref is modified.
   if (FissionExperimentEnrolled()) {

toolkit/xre/test/marionette/test_fission_autostart.py

@@ -57,7 +57,6 @@ class TestFissionAutostart(MarionetteTestCase):
             useRemoteSubframes: win.docShell.nsILoadContext.useRemoteSubframes,
             fissionAutostartSession: Services.prefs.getBoolPref("fission.autostart.session"),
             dynamicFissionAutostart: Services.prefs.getBoolPref("fission.autostart"),
-            nonNativeTheme: Services.prefs.getBoolPref("widget.non-native-theme.enabled"),
           };
         """
         )
@@ -76,14 +75,6 @@ class TestFissionAutostart(MarionetteTestCase):
             "dynamicFissionAutostart": dynamic,
         }
 
-        if expected["fissionExperimentStatus"] in (
-            ExperimentStatus.ENROLLED_CONTROL,
-            ExperimentStatus.ENROLLED_TREATMENT,
-        ):
-            expected["nonNativeTheme"] = True
-        else:
-            expected["nonNativeTheme"] = self.nightly_build
-
         status = self.get_fission_status()
 
         for prop, value in expected.items():