Print out detailed_error_ in various LOG statements in QuicFramer.

net/quic/core/quic_framer.cc

Index: net/quic/core/quic_framer.cc
diff --git a/net/quic/core/quic_framer.cc b/net/quic/core/quic_framer.cc
index a854a063a4b0be1008a532949eec9090a0ec24a5..935669584336ed3dac5edf7bdbcfe8eea0957169 100644
--- a/net/quic/core/quic_framer.cc
+++ b/net/quic/core/quic_framer.cc
@@ -506,7 +506,9 @@ bool QuicFramer::ProcessPacket(const QuicEncryptedPacket& packet) {
   // First parse the public header.
   QuicPacketPublicHeader public_header;
   if (!ProcessPublicHeader(&reader, &public_header)) {
-    DVLOG(1) << ENDPOINT << "Unable to process public header.";
+    DCHECK_NE("", detailed_error_);
+    DVLOG(1) << ENDPOINT
+             << "Unable to process public header. Error: " << detailed_error_;
     DCHECK_NE("", detailed_error_);
     return RaiseError(QUIC_INVALID_PACKET_HEADER);
   }
@@ -573,8 +575,10 @@ bool QuicFramer::ProcessDataPacket(QuicDataReader* encrypted_reader,
                                    size_t buffer_length) {
   QuicPacketHeader header(public_header);
   if (!ProcessUnauthenticatedHeader(encrypted_reader, &header)) {
+    DCHECK_NE("", detailed_error_);
     DVLOG(1) << ENDPOINT
-             << "Unable to process packet header.  Stopping parsing.";
+             << "Unable to process packet header. Stopping parsing. Error: "
+             << detailed_error_;
     return false;
   }
 
@@ -605,7 +609,9 @@ bool QuicFramer::ProcessDataPacket(QuicDataReader* encrypted_reader,
   // Handle the payload.
   if (!ProcessFrameData(&reader, header)) {
     DCHECK_NE(QUIC_NO_ERROR, error_);  // ProcessFrameData sets the error.
-    DLOG(WARNING) << ENDPOINT << "Unable to process frame data.";
+    DCHECK_NE("", detailed_error_);
+    DLOG(WARNING) << ENDPOINT
+                  << "Unable to process frame data. Error: " << detailed_error_;
     return false;
   }
 
@@ -965,6 +971,7 @@ bool QuicFramer::ProcessUnauthenticatedHeader(QuicDataReader* encrypted_reader,
   if (header->public_header.multipath_flag &&
       !IsValidPath(header->path_id, &base_packet_number)) {
     // Stop processing because path is closed.
+    set_detailed_error("Path is closed.");
     return false;
   }
 
@@ -981,6 +988,8 @@ bool QuicFramer::ProcessUnauthenticatedHeader(QuicDataReader* encrypted_reader,
   }
 
   if (!visitor_->OnUnauthenticatedHeader(*header)) {
+    set_detailed_error(
+        "Visitor asked to stop processing of unauthenticated header.");
     return false;
   }
   return true;