Replace QuicheStringPiece with absl::string_view

Tested:
    TAP train for global presubmit queue
    http://test/OCL:335945871:BASE:336020766:1602159631460:96037042
PiperOrigin-RevId: 336093514
Change-Id: I27c7455ff096f2f0d6d8166c312f066b902cb234
diff --git a/quic/test_tools/test_ticket_crypter.cc b/quic/test_tools/test_ticket_crypter.cc
index 4d0d93e..afd2db4 100644
--- a/quic/test_tools/test_ticket_crypter.cc
+++ b/quic/test_tools/test_ticket_crypter.cc
@@ -29,7 +29,7 @@
   return QUICHE_ARRAYSIZE(kTicketPrefix);
 }
 
-std::vector<uint8_t> TestTicketCrypter::Encrypt(quiche::QuicheStringPiece in) {
+std::vector<uint8_t> TestTicketCrypter::Encrypt(absl::string_view in) {
   size_t prefix_len = QUICHE_ARRAYSIZE(kTicketPrefix);
   std::vector<uint8_t> out(prefix_len + in.size());
   memcpy(out.data(), kTicketPrefix, prefix_len);
@@ -37,7 +37,7 @@
   return out;
 }
 
-std::vector<uint8_t> TestTicketCrypter::Decrypt(quiche::QuicheStringPiece in) {
+std::vector<uint8_t> TestTicketCrypter::Decrypt(absl::string_view in) {
   size_t prefix_len = QUICHE_ARRAYSIZE(kTicketPrefix);
   if (fail_decrypt_ || in.size() < prefix_len ||
       memcmp(kTicketPrefix, in.data(), prefix_len) != 0) {
@@ -47,7 +47,7 @@
 }
 
 void TestTicketCrypter::Decrypt(
-    quiche::QuicheStringPiece in,
+    absl::string_view in,
     std::unique_ptr<ProofSource::DecryptCallback> callback) {
   auto decrypted_ticket = Decrypt(in);
   if (run_async_) {