Cast device revocation checking.

components/cast_certificate/cast_cert_validator_test_helpers.h

Index: components/cast_certificate/cast_cert_validator_test_helpers.h
diff --git a/components/cast_certificate/cast_cert_validator_test_helpers.h b/components/cast_certificate/cast_cert_validator_test_helpers.h
index d5281a70707518f5dd68035897d96e58aed5d79c..72cb5034a19649deeb17cc7e3fe00c2f8487f770 100644
--- a/components/cast_certificate/cast_cert_validator_test_helpers.h
+++ b/components/cast_certificate/cast_cert_validator_test_helpers.h
@@ -35,6 +35,10 @@ struct SignatureTestData {
 // |file_name| should be relative to //components/test/data/cast_certificate
 SignatureTestData ReadSignatureTestData(const base::StringPiece& file_name);
 
+// Reads a file from the test data directory
+// (//src/components/test/data/cast_certificate)
+std::string ReadTestFileToString(const base::StringPiece& file_name);
+
 }  // namespace testing
 
 }  // namespace cast_certificate