TextField drag and drop issues

When trying to migrate from Vaadin 7 to 8, I am running into the following issues with drag and drop and TextFields (I haven't tested other targets).

1: effect matching is not performed in Safari -https://github.com/vaadin/framework/issues/9246#issue-226499933
2: even when effect matching is performed, and determines a mismatch, the style -drag-center is applied to the textfield;
3: criteria matching does not appear to be performed;
4: on Safari drops still occur, even if a criteria script returns false;
5: TextFields without DropTargetExtensions can still receive drops;
6: in some cases the TextField cursor is activated whilst dragging over a drop target.

Vaadin: 8.8.2
Browsers: Safari, FireFox, Chrome

Code to illustrate issues:

`public class TextFieldDnDTest extends VerticalLayout {

public TextFieldDnDTest() {

    List<TextField> targets = new ArrayList<>();

    Page page = Page.getCurrent();

    WebBrowser browser = page.getWebBrowser();
    Label browserLabel = new Label("<b>Browser</b><br>" + browser.getBrowserApplication());
    browserLabel.setContentMode(ContentMode.HTML);
    addComponent(browserLabel);

    Panel source = new Panel();
    source.setSizeUndefined();
    addComponent(source);

    VerticalLayout sourceLayout = new VerticalLayout();
    source.setContent(sourceLayout);

    Label sourceLabel = new Label("<b>Source</b> - drag me");
    sourceLabel.setContentMode(ContentMode.HTML);
    sourceLayout.addComponent(sourceLabel);

    DragSourceExtension dragSource = new DragSourceExtension(source);
    dragSource.setEffectAllowed(EffectAllowed.COPY);
    dragSource.setDataTransferText("This is not expected");
    dragSource.setDragData(new String("This is expected"));
    dragSource.setPayload("drop", "true");

    TextField target1 = new TextField("<b>Target</b> - success");
    target1.setCaptionAsHtml(true);
    target1.setPlaceholder("Drop should succeed");
    targets.add(target1);
    addComponent(target1);

    DropTargetExtension dropTarget1 = new DropTargetExtension(target1);
    dropTarget1.setDropEffect(DropEffect.COPY);
    dropTarget1.addDropListener((DropListener) dropEvent -> {
        target1.setValue((String)dropEvent.getDragData().get());
    });

    TextField target2 = new TextField("<b>Target</b> - mismatching effects<br>Why is the style ..-drag-center added on drag enter?");
    target2.setCaptionAsHtml(true);
    target2.setPlaceholder("Drop should fail");
    targets.add(target2);
    addComponent(target2);

    DropTargetExtension dropTarget2 = new DropTargetExtension(target2);
    dropTarget2.setDropEffect(DropEffect.MOVE);
    dropTarget2.addDropListener((DropListener) dropEvent -> {
        target2.setValue(dropEvent.getDataTransferText());
    });

    TextField target3 = new TextField("<b>Target</b> - criteria script returns false<br>Why is the cursor activated?");
    target3.setCaptionAsHtml(true);
    target3.setPlaceholder("Drop should fail");
    targets.add(target3);
    addComponent(target3);

    DropTargetExtension dropTarget3 = new DropTargetExtension(target3);
    dropTarget3.setDropEffect(DropEffect.COPY);
    dropTarget3.setDropCriteriaScript("console.debug(event.dataTransfer); return false;");
    dropTarget3.addDropListener((DropListener) dropEvent -> {
        target3.setValue((String)dropEvent.getDragData().get());
    });

    TextField target4 = new TextField("<b>Target</b> - payload and criteria match");
    target4.setCaptionAsHtml(true);
    target4.setPlaceholder("Drop should succeed");
    targets.add(target4);
    addComponent(target4);

    DropTargetExtension dropTarget4 = new DropTargetExtension(target4);
    dropTarget4.setDropEffect(DropEffect.COPY);
    dropTarget4.setDropCriterion("drop", "true");
    dropTarget4.addDropListener((DropListener) dropEvent -> {
        target4.setValue((String)dropEvent.getDragData().get());
    });

    TextField target5 = new TextField("<b>Target</b> - payload and criteria do not match<br>Why is the style ..-drag-center added on drag enter?");
    target5.setCaptionAsHtml(true);
    target5.setPlaceholder("Drop should fail");
    targets.add(target5);
    addComponent(target5);

    DropTargetExtension dropTarget5 = new DropTargetExtension(target5);
    dropTarget5.setDropEffect(DropEffect.COPY);
    dropTarget5.setDropCriterion("drop", "false");
    dropTarget5.addDropListener((DropListener) dropEvent -> {
        target5.setValue(dropEvent.getDataTransferText());
    });

    TextField target6 = new TextField("<b>Target</b> - no drop target<br>Why is this textfield receiving drops?<br>Why is the cursor activated?");
    target6.setCaptionAsHtml(true);
    target6.setPlaceholder("Target not configured");
    targets.add(target6);
    addComponent(target6);

    Button reset = new Button("<b>Reset</b>");
    reset.setCaptionAsHtml(true);
    reset.addClickListener(event -> {
        targets.forEach(target -> target.setValue(""));
    });
    addComponent(reset);

    targets.forEach(target -> {
        target.addValueChangeListener((HasValue.ValueChangeListener<String>) event -> {
            String value = event.getValue();
            if (value.length() > 0) {
                boolean success = value.equals("This is expected");
                target.addStyleName(success ? "success" : "failure");
                target.removeStyleName(success ? "failure" : "success");
            } else {
                target.removeStyleName("failure");
                target.removeStyleName("success");
            }
        });


    });

    Page.Styles styles = page.getStyles();
    styles.add(".v-textfield.success { background: #00B96FAA; }");
    styles.add(".v-textfield.failure { background: #FF3F50AA; }");
    styles.add(".v-textfield-drag-center { background: #008CF0aa !important; }");
}

}`

Start with the provided TextFieldDnDTest reproduction and run it in Safari, Firefox, and Chrome to compare the six reported drag-and-drop behaviors. Trace the TextField, DragSourceExtension, and DropTargetExtension entry points; done means effect and criteria mismatches prevent drops and drag styling, unconfigured fields do not accept drops, and dragging does not activate the cursor.