Improve ETagRequired error range

[angelozerr]

Improve ETagRequired error range

Fixes #876

Signed-off-by: azerr [email protected]

[angelozerr]

This PR fixes error range for ETAgrequired, the main idea is to higlight the error from the start tag which is broken to the offset reported by Xerces:

The start tag can be broken because:

• it has not an end tag
• it has an end tag but it contains </ which breaks the XML.

As I had to fix CloseStartTagAction which is used for several error code,this PR fixes several issues:

• Prevent code action from exception #900
• Code Action for </ with no matching open tag #889
• CodeAction for ETagUnterminated #880
• Code Action to close root element closing tag inserts wrong closing tag #878

[datho7561]

For cases like this:

<a>
  <c><b>
</a>

the opening < of </a> is highlighted in the error range:

I find this behaviour odd, since the closing tag should appear before </a>. As well, </a> is correct; it closes the <a> tag.

[angelozerr]

the opening < of is highlighted in the error range:

fixed

[angelozerr]

@datho7561 please review my PR (with vscode-xml and see if my code is understandable). Thanks