Release Preview 20 shared desktop, Android and Sargo updates

Restore Gaia settings and media workflows, extend native network adapters, and align the APK payload. Generate French/English changelogs and website entries from the simplified JSON source.

Validation: shared JS and Tundra unit tests; desktop workflows and persistence; signed APK payload parity; Sargo RAM and installed startup with boot readback. Android runtime qualification is recorded separately.

tools/test-appearance.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+"""Check shared appearance changes in an isolated desktop Gaia profile."""
+import importlib.util
+import json
+from pathlib import Path
+import time
+from marionette_client import Client
+
+spec = importlib.util.spec_from_file_location('probe', Path(__file__).with_name('probe-desktop.py'))
+probe = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(probe)
+checks = []
+with Client(2857) as client:
+    probe.register(client)
+    def ev(app, code):
+        result = probe.evaluate(client, app, code)
+        assert 'error' not in result, result
+        return result.get('value')
+    def wait(app, code):
+        for _ in range(80):
+            result = ev(app, code)
+            if result:
+                return result
+            time.sleep(.15)
+        raise AssertionError((app, code))
+    def check(name, result):
+        assert result, name
+        checks.append(name)
+        print(name + ': OK', flush=True)
+    def theme(mode):
+        ev('settings', f'await navigator.mozSettings.createLock().set({{"vulpes.theme":{json.dumps(mode)}}});return true;')
+    ev('system', 'ScreenManager.turnScreenOn(true);if(Service.query("locked"))await Service.request("unlock",{forcibly:true});return true;')
+    ev('system', 'await VulpesCompat.call("apps.launch",{manifestURL:"http://settings.localhost:8765/manifest.webapp"});return true;')
+    wait('settings', 'return document.readyState==="complete";')
+    previous = ev('settings', 'return await VulpesCompat.call("appearance.current",{});')
+    try:
+        ev('settings', 'const s=await new Promise(r=>require(["modules/settings_service"],r));s.navigate("display");return true;')
+        wait('settings', 'return !!document.querySelector("#vulpes-theme");')
+        theme('light')
+        wait('homescreen', 'return document.documentElement.dataset.vulpesTheme==="light";')
+        home = ev('homescreen', 'return [getComputedStyle(document.documentElement).backgroundColor,getComputedStyle(document.body).backgroundColor,getComputedStyle(document.body).backgroundImage];')
+        # Exercise the actual Settings selector rather than only the broker.
+        ev('settings', 'const s=document.getElementById("vulpes-theme");s.value="dark";s.dispatchEvent(new Event("change",{bubbles:true}));return true;')
+        for app in ['settings', 'homescreen', 'system']:
+            check('dark-live-' + app, wait(app, 'return document.documentElement.dataset.vulpesTheme==="dark";'))
+        check('home-background-preserved', ev('homescreen', 'return [getComputedStyle(document.documentElement).backgroundColor,getComputedStyle(document.body).backgroundColor,getComputedStyle(document.body).backgroundImage];') == home)
+        check('readable-display-header', ev('settings', 'const h=document.querySelector("#display gaia-header");return getComputedStyle(h.shadowRoot.querySelector(".inner")).backgroundColor==="rgb(37, 52, 66)" && getComputedStyle(h.querySelector("h1")).color==="rgb(241, 245, 249)";'))
+        check('selector-label-does-not-overlap', ev('settings', 'const label=document.querySelector("#vulpes-theme-label"),l=label.getBoundingClientRect(),s=document.querySelector("#vulpes-theme").getBoundingClientRect();return parseFloat(getComputedStyle(label).height)>0 && l.bottom<=s.top && s.bottom<=document.querySelector("#vulpes-theme-row").getBoundingClientRect().bottom;'))
+        ev('system', 'await VulpesCompat.call("apps.launch",{manifestURL:"http://sms.localhost:8765/manifest.webapp"});return true;')
+        wait('sms', 'return document.readyState==="complete";')
+        old_time = ev('sms', 'setTimeout(()=>location.reload(),50);return performance.timeOrigin;')
+        check('reloaded-app-reads-saved-theme', wait('sms', f'return performance.timeOrigin!=={old_time} && document.documentElement.dataset.vulpesTheme==="dark";'))
+        theme('system')
+        check('system-preference', wait('sms', 'return document.documentElement.dataset.vulpesTheme===(matchMedia("(prefers-color-scheme: dark)").matches?"dark":"light");'))
+        theme('light')
+        check('return-to-light', wait('sms', 'return document.documentElement.dataset.vulpesTheme==="light";'))
+    finally:
+        theme(previous or 'light')
+print(json.dumps({'checks':checks}, ensure_ascii=False, indent=2))