Replace quic_aligned.h with Abseil and C++11 features.

Since alignas() is now officially supported in google3, use it instead of __attribute__((aligned)).

PiperOrigin-RevId: 339158191
Change-Id: Ie5ee589648ff2e3e86ff668e1ab82e887ae45fe1
diff --git a/quic/core/quic_packet_creator.cc b/quic/core/quic_packet_creator.cc
index 3b367d3..12b7e2d 100644
--- a/quic/core/quic_packet_creator.cc
+++ b/quic/core/quic_packet_creator.cc
@@ -12,6 +12,7 @@
 #include <utility>
 
 #include "absl/base/macros.h"
+#include "absl/base/optimization.h"
 #include "absl/strings/string_view.h"
 #include "net/third_party/quiche/src/quic/core/crypto/crypto_protocol.h"
 #include "net/third_party/quiche/src/quic/core/frames/quic_frame.h"
@@ -24,7 +25,6 @@
 #include "net/third_party/quiche/src/quic/core/quic_types.h"
 #include "net/third_party/quiche/src/quic/core/quic_utils.h"
 #include "net/third_party/quiche/src/quic/core/quic_versions.h"
-#include "net/third_party/quiche/src/quic/platform/api/quic_aligned.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_bug_tracker.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_exported_stats.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_flag_utils.h"
@@ -469,7 +469,7 @@
     return;
   }
 
-  QUIC_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize];
+  ABSL_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize];
   QuicOwnedPacketBuffer external_buffer(delegate_->GetPacketBuffer());
 
   if (external_buffer.buffer == nullptr) {
@@ -593,7 +593,7 @@
                 << ": " << SerializedPacketFateToString(packet_.fate) << " of "
                 << EncryptionLevelToString(packet_.encryption_level);
 
-  QUIC_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize];
+  ABSL_CACHELINE_ALIGNED char stack_buffer[kMaxOutgoingPacketSize];
   QuicOwnedPacketBuffer packet_buffer(delegate_->GetPacketBuffer());
 
   if (packet_buffer.buffer == nullptr) {