Add implicit trailing dot domain matching support to URLPattern.

extensions/common/url_pattern.h

Index: extensions/common/url_pattern.h
diff --git a/extensions/common/url_pattern.h b/extensions/common/url_pattern.h
index bcdc7f65d5d0e77bbf5203aacf59e53734ee199a..94199ede5edd880a4101e7ccc7bf7cb6cb2b5687 100644
--- a/extensions/common/url_pattern.h
+++ b/extensions/common/url_pattern.h
@@ -222,6 +222,9 @@ class URLPattern {
   // equivalent literal schemes, otherwise returns the current scheme.
   std::vector<std::string> GetExplicitSchemes() const;
 
+  // Adds or removes trailing dot to properly handle FQDN matching.
+  std::string CanonicalizeHostForMatching(const GURL& url) const;
+
   // A bitmask containing the schemes which are considered valid for this
   // pattern. Parse() uses this to decide whether a pattern contains a valid
   // scheme.