s/.done(/.then(/ since modern es6 track unhandled promise exceptions

src/components/views/elements/AppTile.js

@@ -205,7 +205,7 @@ export default class AppTile extends React.Component {
         if (!this._scalarClient) {
             this._scalarClient = defaultManager.getScalarClient();
         }
-        this._scalarClient.getScalarToken().done((token) => {
+        this._scalarClient.getScalarToken().then((token) => {
             // Append scalar_token as a query param if not already present
             this._scalarClient.scalarToken = token;
             const u = url.parse(this._addWurlParams(this.props.url));

src/components/views/elements/EditableTextContainer.js

@@ -51,7 +51,7 @@ export default class EditableTextContainer extends React.Component {
 
         this.setState({busy: true});
 
-        this.props.getInitialValue().done(
+        this.props.getInitialValue().then(
             (result) => {
                 if (this._unmounted) { return; }
                 this.setState({
@@ -83,7 +83,7 @@ export default class EditableTextContainer extends React.Component {
             errorString: null,
         });
 
-        this.props.onSubmit(value).done(
+        this.props.onSubmit(value).then(
             () => {
                 if (this._unmounted) { return; }
                 this.setState({

src/components/views/elements/ErrorBoundary.js

@@ -54,7 +54,7 @@ export default class ErrorBoundary extends React.PureComponent {
         if (!PlatformPeg.get()) return;
 
         MatrixClientPeg.get().stopClient();
-        MatrixClientPeg.get().store.deleteAllData().done(() => {
+        MatrixClientPeg.get().store.deleteAllData().then(() => {
             PlatformPeg.get().reload();
         });
     };

src/components/views/elements/ImageView.js

@@ -84,7 +84,7 @@ export default class ImageView extends React.Component {
                         title: _t('Error'),
                         description: _t('You cannot delete this image. (%(code)s)', {code: code}),
                     });
-                }).done();
+                }).then();
             },
         });
     };

src/components/views/elements/LanguageDropdown.js

@@ -49,7 +49,7 @@ export default class LanguageDropdown extends React.Component {
             this.setState({langs});
         }).catch(() => {
             this.setState({langs: ['en']});
-        }).done();
+        }).then();
 
         if (!this.props.value) {
             // If no value is given, we start with the first