Add QUIC_EXPORT macros

net/quic/core/crypto/p256_key_exchange.h

Index: net/quic/core/crypto/p256_key_exchange.h
diff --git a/net/quic/core/crypto/p256_key_exchange.h b/net/quic/core/crypto/p256_key_exchange.h
index afa94431db341ca4c26829726e1e3ceac3cae7b6..575dec446997fd0b79c7d76ab7ffffb80f12a313 100644
--- a/net/quic/core/crypto/p256_key_exchange.h
+++ b/net/quic/core/crypto/p256_key_exchange.h
@@ -13,15 +13,15 @@
 #include "base/macros.h"
 #include "base/strings/string_piece.h"
 #include "crypto/openssl_util.h"
-#include "net/base/net_export.h"
 #include "net/quic/core/crypto/key_exchange.h"
+#include "net/quic/platform/api/quic_export.h"
 #include "third_party/boringssl/src/include/openssl/base.h"
 
 namespace net {
 
 // P256KeyExchange implements a KeyExchange using elliptic-curve
 // Diffie-Hellman on NIST P-256.
-class NET_EXPORT_PRIVATE P256KeyExchange : public KeyExchange {
+class QUIC_EXPORT_PRIVATE P256KeyExchange : public KeyExchange {
  public:
   ~P256KeyExchange() override;