| Index: net/base/mime_sniffer_unittest.cc | 
| diff --git a/net/base/mime_sniffer_unittest.cc b/net/base/mime_sniffer_unittest.cc | 
| index a4bde0faf636fd494b4c6b069eaafc4dd66037be..7865350d3ce164ce86578c3eb336e171c00cd84a 100644 | 
| --- a/net/base/mime_sniffer_unittest.cc | 
| +++ b/net/base/mime_sniffer_unittest.cc | 
| @@ -304,13 +304,14 @@ TEST(MimeSnifferTest, FlashTest) { | 
| TEST(MimeSnifferTest, XMLTest) { | 
| // An easy feed to identify. | 
| EXPECT_EQ("application/atom+xml", | 
| -            SniffMimeType("<?xml?><feed", "", "text/xml")); | 
| +            SniffMimeType("<?xml?><feed", std::string(), "text/xml")); | 
| // Don't sniff out of plain text. | 
| EXPECT_EQ("text/plain", | 
| -            SniffMimeType("<?xml?><feed", "", "text/plain")); | 
| +            SniffMimeType("<?xml?><feed", std::string(), "text/plain")); | 
| // Simple RSS. | 
| EXPECT_EQ("application/rss+xml", | 
| -            SniffMimeType("<?xml version='1.0'?>\r\n<rss", "", "text/xml")); | 
| +            SniffMimeType( | 
| +                "<?xml version='1.0'?>\r\n<rss", std::string(), "text/xml")); | 
|  | 
| // The top of CNN's RSS feed, which we'd like to recognize as RSS. | 
| static const char kCNNRSS[] = | 
| @@ -323,39 +324,43 @@ TEST(MimeSnifferTest, XMLTest) { | 
| "version=\"2.0\">"; | 
| // CNN's RSS | 
| EXPECT_EQ("application/rss+xml", | 
| -            SniffMimeType(kCNNRSS, "", "text/xml")); | 
| -  EXPECT_EQ("text/plain", | 
| -            SniffMimeType(kCNNRSS, "", "text/plain")); | 
| +            SniffMimeType(kCNNRSS, std::string(), "text/xml")); | 
| +  EXPECT_EQ("text/plain", SniffMimeType(kCNNRSS, std::string(), "text/plain")); | 
|  | 
| // Don't sniff random XML as something different. | 
| EXPECT_EQ("text/xml", | 
| -            SniffMimeType("<?xml?><notafeed", "", "text/xml")); | 
| +            SniffMimeType("<?xml?><notafeed", std::string(), "text/xml")); | 
| // Don't sniff random plain-text as something different. | 
| EXPECT_EQ("text/plain", | 
| -            SniffMimeType("<?xml?><notafeed", "", "text/plain")); | 
| +            SniffMimeType("<?xml?><notafeed", std::string(), "text/plain")); | 
|  | 
| // Positive test for the two instances we upgrade to XHTML. | 
| EXPECT_EQ("application/xhtml+xml", | 
| SniffMimeType("<html xmlns=\"http://www.w3.org/1999/xhtml\">", | 
| -                          "", "text/xml")); | 
| +                          std::string(), | 
| +                          "text/xml")); | 
| EXPECT_EQ("application/xhtml+xml", | 
| SniffMimeType("<html xmlns=\"http://www.w3.org/1999/xhtml\">", | 
| -                          "", "application/xml")); | 
| +                          std::string(), | 
| +                          "application/xml")); | 
|  | 
| // Following our behavior with HTML, don't call other mime types XHTML. | 
| EXPECT_EQ("text/plain", | 
| SniffMimeType("<html xmlns=\"http://www.w3.org/1999/xhtml\">", | 
| -                          "", "text/plain")); | 
| +                          std::string(), | 
| +                          "text/plain")); | 
| EXPECT_EQ("application/rss+xml", | 
| SniffMimeType("<html xmlns=\"http://www.w3.org/1999/xhtml\">", | 
| -                          "", "application/rss+xml")); | 
| +                          std::string(), | 
| +                          "application/rss+xml")); | 
|  | 
| // Don't sniff other HTML-looking bits as HTML. | 
| EXPECT_EQ("text/xml", | 
| -            SniffMimeType("<html><head>", "", "text/xml")); | 
| +            SniffMimeType("<html><head>", std::string(), "text/xml")); | 
| EXPECT_EQ("text/xml", | 
| SniffMimeType("<foo><html xmlns=\"http://www.w3.org/1999/xhtml\">", | 
| -                          "", "text/xml")); | 
| +                          std::string(), | 
| +                          "text/xml")); | 
|  | 
| } | 
|  | 
|  |