Update WriteHeaders check with request idempotency.

Since in cl:
https://chromium-review.googlesource.com/c/chromium/src/+/2508299
we allow 0-RTT for POST request if the request is idempotent, we update
the DCHECK in net/quic/quic_chromium_client_stream.cc

Change-Id: I02a8a4c6a1da7eb945b65a8453c92957f10cd945
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2565453
Reviewed-by: David Schinazi <dschinazi@chromium.org>
Commit-Queue: Yu Su <yuyansu@google.com>
Cr-Commit-Position: refs/heads/master@{#833563}

net/http/http_network_transaction.cc

@@ -1038,6 +1038,7 @@ int HttpNetworkTransaction::DoSendRequest() {
   send_start_time_ = base::TimeTicks::Now();
   next_state_ = STATE_SEND_REQUEST_COMPLETE;
 
+  stream_->SetRequestIdempotency(request_->idempotency);
   return stream_->SendRequest(request_headers_, &response_, io_callback_);
 }
 

net/http/http_stream.h

@@ -18,6 +18,7 @@
 
 #include "base/macros.h"
 #include "net/base/completion_once_callback.h"
+#include "net/base/idempotency.h"
 #include "net/base/net_error_details.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_export.h"
@@ -187,6 +188,9 @@ class NET_EXPORT_PRIVATE HttpStream {
 
   virtual void SetRequestHeadersCallback(RequestHeadersCallback callback) = 0;
 
+  // Set the idempotency of the request. No-op by default.
+  virtual void SetRequestIdempotency(Idempotency idempotency) {}
+
  private:
   DISALLOW_COPY_AND_ASSIGN(HttpStream);
 };

net/quic/quic_chromium_client_stream.cc

@@ -399,6 +399,15 @@ int QuicChromiumClientStream::Handle::HandleIOComplete(int rv) {
   return net_error_;
 }
 
+void QuicChromiumClientStream::Handle::SetRequestIdempotency(
+    Idempotency idempotency) {
+  idempotency_ = idempotency;
+}
+
+Idempotency QuicChromiumClientStream::Handle::GetRequestIdempotency() const {
+  return idempotency_;
+}
+
 QuicChromiumClientStream::QuicChromiumClientStream(
     quic::QuicStreamId id,
     quic::QuicSpdyClientSessionBase* session,
@@ -541,7 +550,9 @@ size_t QuicChromiumClientStream::WriteHeaders(
   if (!session()->OneRttKeysAvailable()) {
     auto entry = header_block.find(":method");
     DCHECK(entry != header_block.end());
-    DCHECK_NE("POST", entry->second);
+    DCHECK(
+        entry->second != "POST" ||
+        (handle_ != nullptr && handle_->GetRequestIdempotency() == IDEMPOTENT));
   }
   net_log_.AddEvent(
       NetLogEventType::QUIC_CHROMIUM_CLIENT_STREAM_SEND_REQUEST_HEADERS,

net/quic/quic_chromium_client_stream.h

@@ -15,6 +15,7 @@
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "net/base/completion_once_callback.h"
+#include "net/base/idempotency.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_export.h"
 #include "net/base/upload_data_stream.h"
@@ -134,6 +135,11 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream
 
     const NetLogWithSource& net_log() const;
 
+    // Sets the idempotency of the request.
+    void SetRequestIdempotency(Idempotency idempotency);
+    // Returns the idempotency of the request.
+    Idempotency GetRequestIdempotency() const;
+
    private:
     friend class QuicChromiumClientStream;
 
@@ -188,6 +194,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream
     bool is_done_reading_;
     bool is_first_stream_;
     size_t num_bytes_consumed_;
+    Idempotency idempotency_ = DEFAULT_IDEMPOTENCY;
 
     int net_error_;
 

net/quic/quic_http_stream.cc

@@ -791,4 +791,11 @@ int QuicHttpStream::ComputeResponseStatus() const {
   return ERR_QUIC_PROTOCOL_ERROR;
 }
 
+void QuicHttpStream::SetRequestIdempotency(Idempotency idempotency) {
+  if (stream_ == nullptr) {
+    return;
+  }
+  stream_->SetRequestIdempotency(idempotency);
+}
+
 }  // namespace net

net/quic/quic_http_stream.h

@@ -15,6 +15,7 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "net/base/completion_once_callback.h"
+#include "net/base/idempotency.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_timing_info.h"
 #include "net/base/net_export.h"
@@ -66,6 +67,7 @@ class NET_EXPORT_PRIVATE QuicHttpStream : public MultiplexedHttpStream {
       AlternativeService* alternative_service) const override;
   void PopulateNetErrorDetails(NetErrorDetails* details) override;
   void SetPriority(RequestPriority priority) override;
+  void SetRequestIdempotency(Idempotency idempotency) override;
 
   static HttpResponseInfo::ConnectionInfo ConnectionInfoFromQuicVersion(
       quic::ParsedQuicVersion quic_version);