Fixed regression and fragile test for Grid.

- Fixed regression caused by #17423 in IE8
- Fixed fragile tests for focusing spacer content in Grid
- Changed TestCategory for EscalatorBasicClientFeaturesTest from 'escalator' to 'grid'.

Change-Id: I644f85a68fee643e468342093ad537dcd7bf8626

client/src/com/vaadin/client/widgets/Escalator.java

@@ -4871,7 +4871,7 @@ public class Escalator extends Widget implements RequiresResize,
                             .toString();
                     deco.getStyle().setProperty("clip", clip);
                 } else {
-                    deco.getStyle().clearProperty("clip");
+                    deco.getStyle().setProperty("clip", "auto");
                 }
             }
         }

uitest/src/com/vaadin/tests/components/grid/basicfeatures/EscalatorBasicClientFeaturesTest.java

@@ -31,7 +31,7 @@ import com.vaadin.testbench.TestBenchElement;
 import com.vaadin.testbench.parallel.TestCategory;
 import com.vaadin.tests.tb3.MultiBrowserTest;
 
-@TestCategory("escalator")
+@TestCategory("grid")
 public abstract class EscalatorBasicClientFeaturesTest extends MultiBrowserTest {
 
     private static final String LOGICAL_ROW_ATTRIBUTE_NAME = "vLogicalRow";

uitest/src/com/vaadin/tests/components/grid/basicfeatures/escalator/EscalatorSpacerTest.java

@@ -34,6 +34,7 @@ import org.openqa.selenium.WebElement;
 
 import com.vaadin.client.WidgetUtil;
 import com.vaadin.shared.ui.grid.Range;
+import com.vaadin.testbench.TestBenchElement;
 import com.vaadin.testbench.elements.NotificationElement;
 import com.vaadin.testbench.parallel.BrowserUtil;
 import com.vaadin.tests.components.grid.basicfeatures.EscalatorBasicClientFeaturesTest;
@@ -450,7 +451,8 @@ public class EscalatorSpacerTest extends EscalatorBasicClientFeaturesTest {
         selectMenuPath(FEATURES, SPACERS, FOCUSABLE_UPDATER);
         selectMenuPath(FEATURES, SPACERS, ROW_1, SET_100PX);
         tryToTabIntoFocusUpdaterElement();
-        assertEquals("input", getFocusedElement().getTagName());
+        WebElement focusedElement = getFocusedElement();
+        assertEquals("input", focusedElement.getTagName());
     }
 
     @Test
@@ -485,11 +487,9 @@ public class EscalatorSpacerTest extends EscalatorBasicClientFeaturesTest {
     }
 
     private void tryToTabIntoFocusUpdaterElement() {
-        getEscalator().sendKeys( //
-                Keys.TAB, // v-ui v-scrollable
-                Keys.TAB, // menubar
-                Keys.TAB // <input>
-                );
+        ((TestBenchElement) findElement(By.className("gwt-MenuBar"))).focus();
+        WebElement focusedElement = getFocusedElement();
+        focusedElement.sendKeys(Keys.TAB);
     }
 
     private WebElement getChild(WebElement parent, int childIndex) {