fix internal value processing and more tests

Author: rbri

src/main/java/org/htmlunit/html/HtmlTextArea.java

@@ -171,12 +171,16 @@ public final void setText(final String newValue) {
     }
 
     private void setTextInternal(final String newValue) {
+        final String oldValue = getText();
+
         rawValue_ = newValue;
         isValueDirty_ = true;
 
-        final int pos = newValue.length();
-        setSelectionStart(pos);
-        setSelectionEnd(pos);
+        if (!newValue.equals(oldValue)) {
+            final int pos = newValue.length();
+            setSelectionStart(pos);
+            setSelectionEnd(pos);
+        }
     }
 
     /**

src/test/java/org/htmlunit/html/HtmlTextAreaTest.java

@@ -330,7 +330,8 @@ public void typingAndClone() throws Exception {
         HtmlTextArea input = (HtmlTextArea) page.getElementById("foo");
         input = (HtmlTextArea) input.cloneNode(true);
         input.type("4711");
-        assertEquals("4711", input.getTextContent());
+        assertEquals("4711", input.getText());
+        assertEquals("", input.getTextContent());
     }
 
     /**
@@ -355,7 +356,8 @@ public void typingAndReset() throws Exception {
         input.reset();
         input.type("0815");
 
-        assertEquals("0815", input.getTextContent());
+        assertEquals("0815", input.getText());
+        assertEquals("", input.getTextContent());
     }
 
     /**
@@ -380,6 +382,7 @@ public void typingAndSetTextContent() throws Exception {
         input.setTextContent("");
         input.type("0815");
 
-        assertEquals("0815", input.getTextContent());
+        assertEquals("47110815", input.getText());
+        assertEquals("", input.getTextContent());
     }
 }