[154229] Adding XML Editor dita source. Resolves several defects including 153364, 152390, 146639, 144302
diff --git a/docs/org.eclipse.wst.xmleditor.doc.user/topics/twxvalid.dita b/docs/org.eclipse.wst.xmleditor.doc.user/topics/twxvalid.dita
new file mode 100644
index 0000000..35350b6
--- /dev/null
+++ b/docs/org.eclipse.wst.xmleditor.doc.user/topics/twxvalid.dita
@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--Arbortext, Inc., 1988-2005, v.4002-->
+<!DOCTYPE task PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">
+<task id="twxvalid" xml:lang="en-us">
+<title>Validating XML files</title>
+<titlealts>
+<searchtitle>Validating XML files</searchtitle>
+</titlealts>
+<shortdesc>When you validate your XML file, the XML validator will check to
+see that your file is valid and well-formed.</shortdesc>
+<prolog><metadata>
+<keywords><indexterm>XML files<indexterm>validating</indexterm></indexterm>
+</keywords>
+</metadata></prolog>
+<taskbody>
+<context><p>The XML editor will process XML files that are invalid or not
+well-formed. The editor uses heuristics to open a file using the best interpretation
+of the tagging that it can. For example, an element with a missing end tag
+is simply assumed to end at the end of the document. As you make updates to
+a file, the editor incrementally reinterprets your document, changing the
+highlighting, tree view, and so on. Many formation errors are easy to spot
+in the syntax highlighting, so you can easily correct obvious errors on-the-fly.
+However, there will be other cases when it will be beneficial to perform formal
+validation on your documents.</p></context>
+<steps>
+<step><cmd>You can validate your file by selecting it in the Navigator view,
+right-clicking it, and clicking <uicontrol>Validate XML file</uicontrol>.</cmd>
+</step>
+</steps>
+<result><p>Any validation problems are indicated in the Problems view. </p></result>
+<postreq><p>In the Problems view, you can double-click on individual errors,
+and you will be taken to the invalid tag in the file, so that you can make
+corrections. </p><p><b>Note</b>: If you receive an error message indicating
+that the Problems view is full, you can increase the number of error messages
+allowed by selecting <menucascade><uicontrol>Properties</uicontrol><uicontrol>Validation</uicontrol>
+</menucascade> from the project's pop-up menu and specifying the maximum number
+of error messages allowed. You must select the <uicontrol>Override validation
+preferences</uicontrol> check box in order to be able to do this.</p><p>As
+well, you can set up a project's properties so that different types of project
+resources are automatically validated when you save them. From a project's
+pop-up menu select <uicontrol>Properties</uicontrol>, then select <uicontrol>Validation</uicontrol>.
+Any validators you can run against your project will be listed in the Validation
+page.</p></postreq>
+</taskbody>
+<related-links>
+<link href="../../org.eclipse.jst.j2ee.doc.user/topics/tjval.dita" scope="peer">
+<desc>General validation information</desc>
+</link>
+</related-links>
+</task>