fix for unbalanced quotes

pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/rule/security/VfUnescapeElRule.java

@@ -72,13 +72,8 @@ public class VfUnescapeElRule extends AbstractVfRule {
         boolean quoted = false;
 
         if (prevText != null) {
-            if ("'".equals(prevText.jjtGetLastToken()) || "\"".equals(prevText.jjtGetLastToken())) {
+            if (isUnbalanced(prevText.getImage(), "'") || isUnbalanced(prevText.getImage(), "\"")) {
                 quoted = true;
-            } else {
-                if (prevText.getImage() != null
-                        && (prevText.getImage().contains("'") | prevText.getImage().contains("\""))) {
-                    quoted = true;
-                }
             }
         }
         if (quoted) {
@@ -95,6 +90,22 @@ public class VfUnescapeElRule extends AbstractVfRule {
         }
     }
 
+    private boolean isUnbalanced(String image, String pattern) {
+        int occurance = 0;
+        int index = image.lastIndexOf("=");
+        index = image.indexOf(pattern, index + 1);
+        while (index >= 0) {
+            occurance++;
+            index = image.indexOf(pattern, index + 1);
+        }
+
+        if ((occurance % 2) != 0) {
+            return true;
+        }
+
+        return false;
+    }
+
     @Override
     public Object visit(ASTElement node, Object data) {
         if (doesTagSupportEscaping(node)) {