Move quic_flags.h from net/quic/core to net/quic/platform and split into api and impl.

net/quic/core/congestion_control/cubic_test.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/core/congestion_control/cubic.h"
 
 #include <cstdint>
 
-#include "net/quic/core/quic_flags.h"
+#include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_str_cat.h"
 #include "net/quic/test_tools/mock_clock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using std::string;
 
 namespace net {
 namespace test {
 namespace {
 
@@ skipping 350 matching lines @@
     clock_.AdvanceTime(hundred_ms_);
     current_cwnd = cubic_.CongestionWindowAfterAck(current_cwnd, rtt_min,
                                                    clock_.ApproximateNow());
   }
   expected_cwnd = 399;
   EXPECT_EQ(expected_cwnd, current_cwnd);
 }
 
 }  // namespace test
 }  // namespace net