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url/url_parse.h

Index: url/url_parse.h
diff --git a/url/url_parse.h b/url/url_parse.h
index 21033ddbbf6c9a056789564776417cffa2841e79..a5261859558aff9f8c56c99305bd58a0bf0aa423 100644
--- a/url/url_parse.h
+++ b/url/url_parse.h
@@ -332,6 +332,20 @@ URL_EXPORT void ExtractFileName(const base::char16* url,
                                 const Component& path,
                                 Component* file_name);
 
+// Extracts the range of the file extension in the given url. It uses
+// ExtractFileName() to extract the file name first. The file extension is
+// defined all characters following the last dot in the file name, unless the
+// last dot is the first character of the file name.
+//
+// The file extension will be empty if the file name is empty or there is no
+// extension in the file name.
+URL_EXPORT void ExtractFileExtension(const char* url,
+                                     const Component& path,
+                                     Component* file_extension);
+URL_EXPORT void ExtractFileExtension(const base::char16* url,
+                                     const Component& path,
+                                     Component* file_extension);
+
 // Extract the first key/value from the range defined by |*query|. Updates
 // |*query| to start at the end of the extracted key/value pair. This is
 // designed for use in a loop: you can keep calling it with the same query