Include colons in expectedError matches.

If we're doing substring matching, we should at least include the delimiter.

Change-Id: I98bee568140d0304bbb6a2788333dbfca044114c
Reviewed-on: https://boringssl-review.googlesource.com/7420
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index 52729e3..f85175a 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -2516,7 +2516,7 @@
 					},
 				},
 				shouldFail:    true,
-				expectedError: "SIGNATURE",
+				expectedError: ":BAD_SIGNATURE:",
 			})
 		}
 	}
@@ -2542,7 +2542,7 @@
 			},
 		},
 		shouldFail:    true,
-		expectedError: "DECRYPTION_FAILED_OR_BAD_RECORD_MAC",
+		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
 	})
 	// OpenSSL previously had an issue where the first byte of padding in
 	// 255 bytes of padding wasn't checked.
@@ -2557,7 +2557,7 @@
 		},
 		messageLen:    12, // 20 bytes of SHA-1 + 12 == 0 % block size
 		shouldFail:    true,
-		expectedError: "DECRYPTION_FAILED_OR_BAD_RECORD_MAC",
+		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
 	})
 }