CHECK that QuicHttpStream::callback_ is null in any methods which may

net/quic/chromium/quic_http_stream.cc

Index: net/quic/chromium/quic_http_stream.cc
diff --git a/net/quic/chromium/quic_http_stream.cc b/net/quic/chromium/quic_http_stream.cc
index cccf3b5be0ad34bab8fc2d4b524abf83244e7f64..df0a0d6834c977c500694a517df81d2dd15d6a66 100644
--- a/net/quic/chromium/quic_http_stream.cc
+++ b/net/quic/chromium/quic_http_stream.cc
@@ -135,6 +135,7 @@ int QuicHttpStream::InitializeStream(const HttpRequestInfo* request_info,
                                      RequestPriority priority,
                                      const BoundNetLog& stream_net_log,
                                      const CompletionCallback& callback) {
+  CHECK(callback_.is_null());
   DCHECK(!stream_);
   if (!session_)
     return was_handshake_confirmed_ ? ERR_CONNECTION_CLOSED
@@ -253,6 +254,7 @@ int QuicHttpStream::SendRequest(const HttpRequestHeaders& request_headers,
                                 const CompletionCallback& callback) {
   CHECK(!request_body_stream_);
   CHECK(!response_info_);
+  CHECK(callback_.is_null());
   CHECK(!callback.is_null());
   CHECK(response);
 
@@ -316,6 +318,7 @@ UploadProgress QuicHttpStream::GetUploadProgress() const {
 }
 
 int QuicHttpStream::ReadResponseHeaders(const CompletionCallback& callback) {
+  CHECK(callback_.is_null());
   CHECK(!callback.is_null());
 
   if (stream_ == nullptr)
@@ -334,6 +337,11 @@ int QuicHttpStream::ReadResponseHeaders(const CompletionCallback& callback) {
 int QuicHttpStream::ReadResponseBody(IOBuffer* buf,
                                      int buf_len,
                                      const CompletionCallback& callback) {
+  CHECK(callback_.is_null());
+  CHECK(!callback.is_null());
+  CHECK(!user_buffer_.get());
+  CHECK_EQ(0, user_buffer_len_);
+
   if (!stream_) {
     // If the stream is already closed, there is no body to read.
     return response_status_;
@@ -343,10 +351,6 @@ int QuicHttpStream::ReadResponseBody(IOBuffer* buf,
   if (rv != ERR_IO_PENDING)
     return rv;
 
-  CHECK(callback_.is_null());
-  CHECK(!user_buffer_.get());
-  CHECK_EQ(0, user_buffer_len_);
-
   callback_ = callback;
   user_buffer_ = buf;
   user_buffer_len_ = buf_len;