Move IsAboutBlank from url_utils to GURL

url/gurl.h

Index: url/gurl.h
diff --git a/url/gurl.h b/url/gurl.h
index d7d575b1e1633d3ddf95006043042dd7da37befc..ae2c40889f9aa6526307d17cad164c247ad547f1 100644
--- a/url/gurl.h
+++ b/url/gurl.h
@@ -203,6 +203,10 @@ class URL_EXPORT GURL {
   // by calling SchemeIsFile[System].
   bool IsStandard() const;
 
+  // Returns true when the url is of the form about:blank, about:blank?foo or
+  // about:blank/#foo.
+  bool IsAboutBlank() const;
+
   // Returns true if the given parameter (should be lower-case ASCII to match
   // the canonicalized scheme) is the scheme for this URL. Do not include a
   // colon.