Add CHECK's to debug QuicStreamSequencerBuffer in weird state. Add a destruction indicator to detec…

net/quic/core/quic_stream_sequencer_test.cc

Index: net/quic/core/quic_stream_sequencer_test.cc
diff --git a/net/quic/core/quic_stream_sequencer_test.cc b/net/quic/core/quic_stream_sequencer_test.cc
index ab6a257ade0f9d685f7135c0be7dac6f9f6b35a1..79db610f46bde66057fdfce4bc7ec2d73cc0afc1 100644
--- a/net/quic/core/quic_stream_sequencer_test.cc
+++ b/net/quic/core/quic_stream_sequencer_test.cc
@@ -659,31 +659,16 @@ TEST_F(QuicStreamSequencerTest, OutOfOrderTimestamps) {
   EXPECT_EQ(0u, sequencer_->NumBytesBuffered());
 }
 
-// TODO(danzh): Figure out the way to implement this test case without the use
-// of unsupported StringPiece constructor.
-#if 0
 TEST_F(QuicStreamSequencerTest, OnStreamFrameWithNullSource) {
   // Pass in a frame with data pointing to null address, expect to close
   // connection with error.
-  StringPiece source(nullptr, 5u);
+  StringPiece source;
+  source.set(nullptr, 5u);
   QuicStreamFrame frame(kClientDataStreamId1, false, 1, source);
   EXPECT_CALL(stream_, CloseConnectionWithDetails(
                            QUIC_STREAM_SEQUENCER_INVALID_STATE, _));
   sequencer_->OnStreamFrame(frame);
 }
-#endif
-
-TEST_F(QuicStreamSequencerTest, ReadvError) {
-  EXPECT_CALL(stream_, OnDataAvailable());
-  string source(100, 'a');
-  OnFrame(0u, source.data());
-  EXPECT_EQ(source.length(), sequencer_->NumBytesBuffered());
-  // Pass in a null iovec, expect to tear down connection.
-  EXPECT_CALL(stream_, CloseConnectionWithDetails(
-                           QUIC_STREAM_SEQUENCER_INVALID_STATE, _));
-  iovec iov{nullptr, 512};
-  sequencer_->Readv(&iov, 1u);
-}
 
 }  // namespace
 }  // namespace test