Provide a libevent-based version of QuicEventLoop

Rationale:
- libevent has scalable backends for all platforms, including Windows
- libevent has a feature to wake up an event loop from different threads; this is really hard to implement consistently across all platforms.

Also fix some build failures under --config=gce

PiperOrigin-RevId: 459268214
diff --git a/build/source_list.bzl b/build/source_list.bzl
index 0bb50d2..673c5b7 100644
--- a/build/source_list.bzl
+++ b/build/source_list.bzl
@@ -1002,6 +1002,7 @@
     "epoll_server/platform/api/epoll_address_test_utils.h",
     "epoll_server/platform/api/epoll_expect_bug.h",
     "epoll_server/platform/api/epoll_test.h",
+    "quic/bindings/quic_libevent.h",
     "quic/test_tools/quic_client_peer.h",
     "quic/test_tools/quic_mock_syscall_wrapper.h",
     "quic/test_tools/quic_server_peer.h",
@@ -1011,6 +1012,7 @@
 ]
 epoll_test_support_srcs = [
     "epoll_server/fake_simple_epoll_server.cc",
+    "quic/bindings/quic_libevent.cc",
     "quic/test_tools/quic_client_peer.cc",
     "quic/test_tools/quic_mock_syscall_wrapper.cc",
     "quic/test_tools/quic_server_peer.cc",
@@ -1098,6 +1100,7 @@
     "http2/test_tools/http2_frame_builder_test.cc",
     "http2/test_tools/http2_random_test.cc",
     "http2/test_tools/random_decoder_test_base_test.cc",
+    "quic/bindings/quic_libevent_test.cc",
     "quic/core/congestion_control/bandwidth_sampler_test.cc",
     "quic/core/congestion_control/bbr2_simulator_test.cc",
     "quic/core/congestion_control/bbr_sender_test.cc",