Move IsAboutBlank from url_utils to GURL

url/gurl.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef URL_GURL_H_
 #define URL_GURL_H_
 
 #include <stddef.h>
 
 #include <iosfwd>
@@ skipping 185 matching lines @@
   // returned.
   GURL GetAsReferrer() const;
 
   // Returns true if the scheme for the current URL is a known "standard-format"
   // scheme. A standard-format scheme adheres to what RFC 3986 calls "generic
   // URI syntax" (https://tools.ietf.org/html/rfc3986#section-3). This includes
   // file: and filesystem:, which some callers may want to filter out explicitly
   // 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.
   bool SchemeIs(base::StringPiece lower_ascii_scheme) const;
 
   // Returns true if the scheme is "http" or "https".
   bool SchemeIsHTTPOrHTTPS() const;
 
   // Returns true if the scheme is valid for use as a referrer.
   bool SchemeIsValidForReferrer() const;
@@ skipping 245 matching lines @@
 URL_EXPORT bool operator==(const GURL& x, const GURL& y);
 URL_EXPORT bool operator!=(const GURL& x, const GURL& y);
 
 // Equality operator for comparing raw spec_. This should be used in place of
 // url == GURL(spec) where |spec| is known (i.e. constants). This is to prevent
 // needlessly re-parsing |spec| into a temporary GURL.
 URL_EXPORT bool operator==(const GURL& x, const base::StringPiece& spec);
 URL_EXPORT bool operator!=(const GURL& x, const base::StringPiece& spec);
 
 #endif  // URL_GURL_H_