Make GURL::GetAsReferrer match KURL::strippedForUseAsReferrer

Esp. if it's an invalid URL or otherwise not a valid referrer (i.e.
non-HTTP(S)) return an empty URL.

BUG=422871
R=brettw@chromium.org

Review URL: https://codereview.chromium.org/736403002

Cr-Commit-Position: refs/heads/master@{#305475}

3 files changed, 10 insertions, 3 deletions

diff --git a/url/gurl.cc b/url/gurl.cc
index b7374b1..b580125 100644
--- a/url/gurl.cc
+++ b/url/gurl.cc
@@ -322,8 +322,10 @@ GURL GURL::GetOrigin() const {
 }
 
 GURL GURL::GetAsReferrer() const {
-  if (!is_valid_ ||
-      (!has_ref() && !has_username() && !has_password()))
+  if (!is_valid_ || !SchemeIsHTTPOrHTTPS())
+    return GURL();
+
+  if (!has_ref() && !has_username() && !has_password())
     return GURL(*this);
 
   url::Replacements<char> replacements;
diff --git a/url/gurl.h b/url/gurl.h
index 1d388cd..f370934 100644
--- a/url/gurl.h
+++ b/url/gurl.h
@@ -198,7 +198,8 @@ class URL_EXPORT GURL {
 
   // A helper function to return a GURL stripped from the elements that are not
   // supposed to be sent as HTTP referrer: username, password and ref fragment.
-  // For invalid URLs the original URL will be returned.
+  // For invalid URLs or URLs that no valid referrers, an empty URL will be
+  // returned.
   GURL GetAsReferrer() const;
 
   // Returns true if the scheme for the current URL is a known "standard"
diff --git a/url/gurl_unittest.cc b/url/gurl_unittest.cc
index 3e94550..a699189 100644
--- a/url/gurl_unittest.cc
+++ b/url/gurl_unittest.cc
@@ -343,6 +343,10 @@ TEST(GURLTest, GetAsReferrer) {
     {"http://:pass@www.google.com", "http://www.google.com/"},
     {"http://:@www.google.com", "http://www.google.com/"},
     {"http://www.google.com/temp/foo?q#b", "http://www.google.com/temp/foo?q"},
+    {"not a url", ""},
+    {"unknown-scheme://foo.html", ""},
+    {"file:///tmp/test.html", ""},
+    {"https://www.google.com", "https://www.google.com/"},
   };
   for (size_t i = 0; i < arraysize(cases); i++) {
     GURL url(cases[i].input);