Deprecate --quic_ignore_invalid_error_code.

net/quic/quic_framer.cc

Index: net/quic/quic_framer.cc
diff --git a/net/quic/quic_framer.cc b/net/quic/quic_framer.cc
index 79862b4e9b3f8bacac1e603fd7255e86170e4876..fac4e894a4e71702e454d3cf760fa9212efe5efc 100644
--- a/net/quic/quic_framer.cc
+++ b/net/quic/quic_framer.cc
@@ -1659,13 +1659,8 @@ bool QuicFramer::ProcessRstStreamFrame(QuicDataReader* reader,
   }
 
   if (error_code >= QUIC_STREAM_LAST_ERROR) {
-    if (FLAGS_quic_ignore_invalid_error_code) {
-      // Ignore invalid stream error code if any.
-      error_code = QUIC_STREAM_LAST_ERROR;
-    } else {
-      set_detailed_error("Invalid rst stream error code.");
-      return false;
-    }
+    // Ignore invalid stream error code if any.
+    error_code = QUIC_STREAM_LAST_ERROR;
   }
 
   frame->error_code = static_cast<QuicRstStreamErrorCode>(error_code);
@@ -1681,13 +1676,8 @@ bool QuicFramer::ProcessConnectionCloseFrame(QuicDataReader* reader,
   }
 
   if (error_code >= QUIC_LAST_ERROR) {
-    if (FLAGS_quic_ignore_invalid_error_code) {
-      // Ignore invalid QUIC error code if any.
-      error_code = QUIC_LAST_ERROR;
-    } else {
-      set_detailed_error("Invalid error code.");
-      return false;
-    }
+    // Ignore invalid QUIC error code if any.
+    error_code = QUIC_LAST_ERROR;
   }
 
   frame->error_code = static_cast<QuicErrorCode>(error_code);
@@ -1711,13 +1701,8 @@ bool QuicFramer::ProcessGoAwayFrame(QuicDataReader* reader,
   }
 
   if (error_code >= QUIC_LAST_ERROR) {
-    if (FLAGS_quic_ignore_invalid_error_code) {
-      // Ignore invalid QUIC error code if any.
-      error_code = QUIC_LAST_ERROR;
-    } else {
-      set_detailed_error("Invalid error code.");
-      return false;
-    }
+    // Ignore invalid QUIC error code if any.
+    error_code = QUIC_LAST_ERROR;
   }
   frame->error_code = static_cast<QuicErrorCode>(error_code);