Conform more of the code base to strict null checking (#10147)

* Conform more of the code base to strict null checking

* More strict fixes

* More strict work

* Fix missing optional type

* Iterate

src/components/views/voip/AudioFeed.tsx

@@ -118,7 +118,7 @@ export default class AudioFeed extends React.Component<IProps, IState> {
         this.playMedia();
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         // Do not render the audio element if there is no audio track
         if (this.state.audioMuted) return null;
 

src/components/views/voip/DialPad.tsx

@@ -39,7 +39,7 @@ class DialPadButton extends React.PureComponent<IButtonProps> {
         this.props.onButtonPress(this.props.digit, ev);
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         switch (this.props.kind) {
             case DialPadButtonKind.Digit:
                 return (
@@ -68,7 +68,7 @@ interface IProps {
 }
 
 export default class Dialpad extends React.PureComponent<IProps> {
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const buttonNodes = [];
 
         for (let i = 0; i < BUTTONS.length; i++) {

src/components/views/voip/DialPadModal.tsx

@@ -82,7 +82,7 @@ export default class DialpadModal extends React.PureComponent<IProps, IState> {
         this.props.onFinished(true);
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const backspaceButton = <DialPadBackspaceButton onBackspacePress={this.onDeletePress} />;
 
         // Only show the backspace button if the field has content

src/components/views/voip/LegacyCallView.tsx

@@ -549,7 +549,7 @@ export default class LegacyCallView extends React.Component<IProps, IState> {
         }
     }
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const { call, secondaryCall, pipMode, showApps, onMouseDownOnHeader } = this.props;
         const { sidebarShown, sidebarFeeds } = this.state;
 

src/components/views/voip/LegacyCallView/LegacyCallViewButtons.tsx

@@ -217,7 +217,7 @@ export default class LegacyCallViewButtons extends React.Component<IProps, IStat
         this.setState({ showMoreMenu: false });
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const callControlsClasses = classNames("mx_LegacyCallViewButtons", {
             mx_LegacyCallViewButtons_hidden: !this.state.visible,
         });

src/components/views/voip/LegacyCallViewForRoom.tsx

@@ -83,7 +83,7 @@ export default class LegacyCallViewForRoom extends React.Component<IProps, IStat
         this.props.resizeNotifier.stopResizing();
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         if (!this.state.call) return null;
 
         return (

src/components/views/voip/LegacyCallViewSidebar.tsx

@@ -28,7 +28,7 @@ interface IProps {
 }
 
 export default class LegacyCallViewSidebar extends React.Component<IProps> {
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const feeds = this.props.feeds.map((feed) => {
             return (
                 <VideoFeed

src/components/views/voip/VideoFeed.tsx

@@ -177,7 +177,7 @@ export default class VideoFeed extends React.PureComponent<IProps, IState> {
         }
     };
 
-    public render(): JSX.Element {
+    public render(): React.ReactNode {
         const { pipMode, primary, secondary, feed } = this.props;
 
         const wrapperClasses = classnames("mx_VideoFeed", {