feat(ios) add ability to go PiP while screen sharing

react/features/base/flags/constants.ts

@@ -160,6 +160,12 @@ export const OVERFLOW_MENU_ENABLED = 'overflow-menu.enabled';
  */
 export const PIP_ENABLED = 'pip.enabled';
 
+/**
+ * Flag indicating if Picture-in-Picture button should be shown while screen sharing.
+ * Default: disabled (false).
+ */
+export const PIP_WHILE_SCREEN_SHARING_ENABLED = 'pip-while-screen-sharing.enabled';
+
 /**
  * Flag indicating if the prejoin page should be enabled.
  * Default: enabled (true).

react/features/mobile/picture-in-picture/components/PictureInPictureButton.js

@@ -2,7 +2,7 @@
 
 import { NativeModules, Platform } from 'react-native';
 
-import { PIP_ENABLED, getFeatureFlag } from '../../../base/flags';
+import { PIP_ENABLED, PIP_WHILE_SCREEN_SHARING_ENABLED, getFeatureFlag } from '../../../base/flags';
 import { translate } from '../../../base/i18n';
 import { IconArrowDown } from '../../../base/icons';
 import { connect } from '../../../base/redux';
@@ -63,8 +63,10 @@ class PictureInPictureButton extends AbstractButton<Props, *> {
  * }}
  */
 function _mapStateToProps(state): Object {
-    const flag = Boolean(getFeatureFlag(state, PIP_ENABLED));
-    let enabled = flag && !isLocalVideoTrackDesktop(state);
+    const pipEnabled = Boolean(getFeatureFlag(state, PIP_ENABLED));
+    const pipWhileScreenSharingEnabled = getFeatureFlag(state, PIP_WHILE_SCREEN_SHARING_ENABLED, false);
+
+    let enabled = pipEnabled && (!isLocalVideoTrackDesktop(state) || pipWhileScreenSharingEnabled);
 
     // Override flag for Android, since it might be unsupported.
     if (Platform.OS === 'android' && !NativeModules.PictureInPicture.SUPPORTED) {