Add flag to enable/disable affiliaton based matching.

components/password_manager/core/browser/affiliation_utils.h

Index: components/password_manager/core/browser/affiliation_utils.h
diff --git a/components/password_manager/core/browser/affiliation_utils.h b/components/password_manager/core/browser/affiliation_utils.h
index 5a25b53e134cf5594ffb878895df13cb7e352d1f..8054346d78206788c6e1fbe0e2379758ca080445 100644
--- a/components/password_manager/core/browser/affiliation_utils.h
+++ b/components/password_manager/core/browser/affiliation_utils.h
@@ -53,6 +53,10 @@
 #include "base/time/time.h"
 #include "url/url_parse.h"
 
+namespace base {
+class CommandLine;
+}  // namespace base
+
 namespace password_manager {
 
 // Encapsulates a facet URI in canonical form.
@@ -161,6 +165,11 @@ struct AffiliatedFacetsWithUpdateTime {
 bool AreEquivalenceClassesEqual(const AffiliatedFacets& a,
                                 const AffiliatedFacets& b);
 
+// Returns whether or not affiliation based matching is enabled, either via
+// command line flags or field trials. The command line flag, if present, always
+// takes precedence.
+bool IsAffiliationBasedMatchingEnabled(const base::CommandLine& command_line);
+
 // For logging use only.
 std::ostream& operator<<(std::ostream& os, const FacetURI& facet_uri);