Attempt to normalize XML data-streams when comparing for equality.

Used during solution install/reinstall to determine if changes have been
made. Fedora selectively strips newline characters within actual content.
Now we normalize the two data-streams such that all newlines are made spaces
and any preceding/trailing white-space within the document is removed.

For Issue:
https://dgi.ontimenow.com/viewitem.aspx?id=1989&type=features&force_use_number=false

includes/solution_packs.inc

@@ -431,12 +431,18 @@ function islandora_check_object_status(AbstractObject $object_definition) {
       // we need to replace the info:fedora namespace, as C14N hates it.
       // C14N also doesn't normalize whitespace at the end of lines and Fedora
       // may add some whitespace on some lines.
+      $xsl = new DOMDocument();
+      $xsl->load(drupal_get_path('module', 'islandora') . '/xml/strip_newlines_and_whitespace.xsl');
+      $xslt = new XSLTProcessor();
+      $xslt->importStyleSheet($xsl);
       $object_definition_dom = new DOMDocument();
       $object_definition_dom->preserveWhiteSpace = FALSE;
       $object_definition_dom->loadXML(str_replace('info:', 'http://', $ds->content));
+      $object_definition_dom = $xslt->transformToDoc($object_definition_dom);
       $object_actual_dom = new DOMDocument();
       $object_actual_dom->preserveWhiteSpace = FALSE;
       $object_actual_dom->loadXML(str_replace('info:', 'http://', $existing_object[$ds->id]->content));
+      $object_actual_dom = $xslt->transformToDoc($object_actual_dom);
 
       // Fedora changes the xml structure so we need to cannonize it.
       if ($object_actual_dom->C14N() != $object_definition_dom->C14N()) {

xml/strip_newlines_and_whitespace.xsl

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes" media-type="text/xml"/>
+  <xsl:strip-space elements="*"/>
+  <xsl:template match="node()|@*">
+    <xsl:copy>
+      <xsl:apply-templates select="node()|@*"/>
+    </xsl:copy>
+  </xsl:template>
+  <xsl:template match="text()">
+    <xsl:value-of select="translate(., '&#xA;', ' ')"/>
+  </xsl:template>
+</xsl:stylesheet>