Make HasAutocompleteAttributeValue handle multi-valued strings

components/autofill/core/common/autofill_util.h

Index: components/autofill/core/common/autofill_util.h
diff --git a/components/autofill/core/common/autofill_util.h b/components/autofill/core/common/autofill_util.h
index 519b3cbe4f3b33563352796517d30fee1a4f7396..fccd473af203a6aaa5ce9d2a8038684437e50071 100644
--- a/components/autofill/core/common/autofill_util.h
+++ b/components/autofill/core/common/autofill_util.h
@@ -7,6 +7,9 @@
 
 #include <stddef.h>
 
+#include <string>
+#include <vector>
+
 #include "base/strings/string16.h"
 #include "components/autofill/core/common/form_field_data.h"
 
@@ -51,6 +54,12 @@ void SetCheckStatus(FormFieldData* form_field_data,
                     bool isCheckable,
                     bool isChecked);
 
+// Lowercases and tokenizes a given |attribute| string.
+// Considers any ASCII whitespace character as a possible separator.
+// Also ignores empty tokens, resulting in a collapsing of whitespace.
+std::vector<std::string> LowercaseAndTokenizeAttributeString(
+    const std::string& attribute);
+
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_UTIL_H_