Invalid chars should not be allowed as first character in custom element name

LayoutTests/fast/dom/custom/element-names.html

Index: LayoutTests/fast/dom/custom/element-names.html
diff --git a/LayoutTests/fast/dom/custom/element-names.html b/LayoutTests/fast/dom/custom/element-names.html
index 2fc6408112b616296bfa69d3eae5b91b1c8db2b7..56d4db0676debf85e9c2b43e318e32f3c736f036 100644
--- a/LayoutTests/fast/dom/custom/element-names.html
+++ b/LayoutTests/fast/dom/custom/element-names.html
@@ -17,7 +17,10 @@ test(function () {
         // Reserved names:
         // hyphen-containing names from the applicable specifications,
         // namely the SVG and the MathML.
-        'annotation-xml'
+        'annotation-xml',

[dglazkov, 2014/11/06 05:52:43]

What about test expectations?

[deepak.sa, 2014/11/06 06:20:02]

Test expectation file for this file has been removed earlier.
CL: https://codereview.chromium.org/332583002/

This is done inorder to prevent file comparison when test runner can directly
check the output.

[deepak.sa, 2014/11/06 06:38:38]

CL in which test expectations were removed :
https://codereview.chromium.org/328243002

+        // names containing colon
+        ':-xfoo',
+        'xfoo-:yfoo'
     ];
 
     for (var i = 0; i < invalidNames.length; i++) {