[java] improve error message for unsuccessfully submitting form

Author: titusfortner

java/src/org/openqa/selenium/remote/RemoteWebElement.java

@@ -21,6 +21,7 @@
 import org.openqa.selenium.Beta;
 import org.openqa.selenium.By;
 import org.openqa.selenium.Dimension;
+import org.openqa.selenium.JavascriptException;
 import org.openqa.selenium.OutputType;
 import org.openqa.selenium.Point;
 import org.openqa.selenium.Rectangle;
@@ -79,7 +80,12 @@ public void click() {
 
   @Override
   public void submit() {
-    execute(DriverCommand.SUBMIT_ELEMENT(id));
+    try {
+      execute(DriverCommand.SUBMIT_ELEMENT(id));
+    } catch (JavascriptException ex) {
+      String message = "To submit an element, it must be nested inside a form element";
+      throw new UnsupportedOperationException(message);
+    }
   }
 
   @Override

java/test/org/openqa/selenium/FormHandlingTest.java

@@ -83,7 +83,7 @@ public void testShouldSubmitAFormWhenAnyElementWithinThatFormIsSubmitted() {
   public void testShouldNotBeAbleToSubmitAFormThatDoesNotExist() {
     driver.get(pages.formPage);
     WebElement element = driver.findElement(By.name("SearchableText"));
-    assertThatExceptionOfType(JavascriptException.class).isThrownBy(element::submit);
+    assertThatExceptionOfType(UnsupportedOperationException.class).isThrownBy(element::submit);
   }
 
   @Test
@@ -282,14 +282,10 @@ public void testCanClickOnAnExternalImplicitSubmitButton() {
 
   @Test
   public void canSubmitFormWithSubmitButtonIdEqualToSubmit() {
-    String blank = appServer.create(new Page().withTitle("Submitted Successfully!"));
-    driver.get(appServer.create(new Page().withBody(
-        String.format("<form action='%s'>", blank),
-        "  <input type='submit' id='submit' value='Submit'>",
-        "</form>")));
-
-    driver.findElement(By.id("submit")).submit();
-    wait.until(titleIs("Submitted Successfully!"));
+    driver.get(pages.formPage);
+    driver.findElement(By.id("submit")).click();
+    wait.until(titleIs("We Arrive Here"));
+    assertThat(driver.getTitle()).isEqualTo("We Arrive Here");
   }
 
   @Test