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.

gaia/apps/camera/js/views/viewfinder.js

@@ -205,6 +205,9 @@ module.exports = View.extend({
    */
   updatePreview: function(preview, sensorAngle, mirrored) {
     if (!preview) { return; }
+    // An embedded app can initialize before its window is visible.
+    this.getSize();
+    if (!this.width || !this.height) { return; }
     var aspect;
 
     // Invert dimensions if the camera's `sensorAngle` is