Bug 1647522 - [1.0] Dispatch onFullscreen without metadata when there is an existing media session. r=geckoview-reviewers,agi

Differential Revision: https://phabricator.services.mozilla.com/D91476

mobile/android/chrome/geckoview/GeckoViewMediaControlChild.js

@@ -55,7 +55,7 @@ class GeckoViewMediaControl extends GeckoViewChildModule {
 
     if (element && !mediaElement) {
       // Non-media element fullscreen.
-      return;
+      debug`No fullscreen media element found.`;
     }
 
     const message = {

mobile/android/geckoview/src/main/java/org/mozilla/geckoview/MediaSession.java

@@ -305,16 +305,19 @@ public class MediaSession {
 
         /**
          * The duration of the media in seconds.
+         * 0.0 if unknown.
          */
         public final double duration;
 
         /**
          * The width of the video in device pixels.
+         * 0 if unknown.
          */
         public final long width;
 
         /**
          * The height of the video in device pixels.
+         * 0 if unknown.
          */
         public final long height;
 
@@ -726,7 +729,8 @@ public class MediaSession {
                 final long features = Feature.fromBundle(
                         message.getBundle("features"));
                 delegate.onFeatures(mSession, mMediaSession, features);
-            } else if (FULLSCREEN_EVENT.equals(event)) {
+            } else if (FULLSCREEN_EVENT.equals(event) &&
+                    mMediaSession.isActive()) {
                 final boolean enabled = message.getBoolean("enabled");
                 final ElementMetadata meta =
                         ElementMetadata.fromBundle(