[Cronet] Make delaying sending request headers explicit in bidirectional stream

net/http/bidirectional_stream_unittest.cc

Index: net/http/bidirectional_stream_unittest.cc
diff --git a/net/http/bidirectional_stream_unittest.cc b/net/http/bidirectional_stream_unittest.cc
index 9fa41cf62a693e7c8fefe236761cbe22cf2461eb..67405cea8446831017ebe2861e2b18d1d73722e7 100644
--- a/net/http/bidirectional_stream_unittest.cc
+++ b/net/http/bidirectional_stream_unittest.cc
@@ -58,8 +58,7 @@ class TestDelegateBase : public BidirectionalStream::Delegate {
         on_data_sent_count_(0),
         do_not_start_read_(false),
         run_until_completion_(false),
-        not_expect_callback_(false),
-        disable_auto_flush_(false) {}
+        not_expect_callback_(false) {}
 
   ~TestDelegateBase() override {}
 
@@ -111,8 +110,6 @@ class TestDelegateBase : public BidirectionalStream::Delegate {
       loop_->Quit();
   }
 
-  void DisableAutoFlush() { disable_auto_flush_ = true; }
-
   void Start(std::unique_ptr<BidirectionalStreamRequestInfo> request_info,
              HttpNetworkSession* session) {
     stream_.reset(new BidirectionalStream(std::move(request_info), session,
@@ -126,7 +123,7 @@ class TestDelegateBase : public BidirectionalStream::Delegate {
              const CompletionCallback& cb) {
     callback_ = cb;
     stream_.reset(new BidirectionalStream(std::move(request_info), session,
-                                          disable_auto_flush_, this,
+                                          /*ignored*/ false, this,
                                           std::move(timer_)));
     if (run_until_completion_)
       loop_->Run();
@@ -222,7 +219,6 @@ class TestDelegateBase : public BidirectionalStream::Delegate {
   // This is to ensure that delegate callback is not invoked synchronously when
   // calling into |stream_|.
   bool not_expect_callback_;
-  bool disable_auto_flush_;
 
   CompletionCallback callback_;
   DISALLOW_COPY_AND_ASSIGN(TestDelegateBase);
@@ -759,7 +755,6 @@ TEST_F(BidirectionalStreamTest, TestCoalesceSmallDataBuffers) {
   std::unique_ptr<TestDelegateBase> delegate(new TestDelegateBase(
       read_buffer.get(), kReadBufferSize, base::WrapUnique(timer)));
   delegate->set_do_not_start_read(true);
-  delegate->DisableAutoFlush();
   TestCompletionCallback callback;
   delegate->Start(std::move(request_info), http_session_.get(),
                   callback.callback());