Delegate crc32 calculation to abseil

To reduce number of third_party dependencies of the dcsctp library.

Bug: None
Change-Id: I251d24cc214860342abcc73cdadaf61e3cd02941
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/452180
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#47034}

DEPS

diff --git a/DEPS b/DEPS
index 98f788e..8451e1b 100644
--- a/DEPS
+++ b/DEPS
@@ -1352,6 +1352,7 @@
   "+absl/cleanup/cleanup.h",
   "+absl/container",
   "-absl/container/fixed_array.h",
+  "+absl/crc",
   "+absl/functional/any_invocable.h",
   "+absl/functional/bind_front.h",
   "+absl/memory/memory.h",

g3doc/abseil-in-webrtc.md

diff --git a/g3doc/abseil-in-webrtc.md b/g3doc/abseil-in-webrtc.md
index af305cb..fd74182 100644
--- a/g3doc/abseil-in-webrtc.md
+++ b/g3doc/abseil-in-webrtc.md
@@ -40,6 +40,7 @@
 * The macros in `absl/base/attributes.h`, `absl/base/config.h` and
   `absl/base/macros.h`.
 * `absl/numeric/bits.h`
+* `absl/crc`
 * Single argument `absl::StrCat`
 
 * ABSL_FLAG is allowed in tests and tools, but disallowed in in non-test code.

net/dcsctp/packet/BUILD.gn

diff --git a/net/dcsctp/packet/BUILD.gn b/net/dcsctp/packet/BUILD.gn
index e924893..852788b 100644
--- a/net/dcsctp/packet/BUILD.gn
+++ b/net/dcsctp/packet/BUILD.gn
@@ -47,7 +47,9 @@
 rtc_library("crc32c") {
   deps = [
     "../../../api:array_view",
-    "//third_party/crc32c",
+    "//third_party/abseil-cpp/absl/crc:crc32c",
+    "//third_party/abseil-cpp/absl/numeric:bits",
+    "//third_party/abseil-cpp/absl/strings:string_view",
   ]
   sources = [
     "crc32c.cc",

net/dcsctp/packet/DEPS

diff --git a/net/dcsctp/packet/DEPS b/net/dcsctp/packet/DEPS
deleted file mode 100644
index 206b405..0000000
--- a/net/dcsctp/packet/DEPS
+++ /dev/null
@@ -1,3 +0,0 @@
-include_rules = [
-    "+third_party/crc32c",
-]

net/dcsctp/packet/crc32c.cc

diff --git a/net/dcsctp/packet/crc32c.cc b/net/dcsctp/packet/crc32c.cc
index 8318b0d..a55749b 100644
--- a/net/dcsctp/packet/crc32c.cc
+++ b/net/dcsctp/packet/crc32c.cc
@@ -11,20 +11,16 @@
 
 #include <cstdint>
 
+#include "absl/crc/crc32c.h"
+#include "absl/numeric/bits.h"
+#include "absl/strings/string_view.h"
 #include "api/array_view.h"
-#include "third_party/crc32c/src/include/crc32c/crc32c.h"
 
 namespace dcsctp {
 
 uint32_t GenerateCrc32C(webrtc::ArrayView<const uint8_t> data) {
-  uint32_t crc32c = crc32c_value(data.data(), data.size());
-
-  // Byte swapping for little endian byte order:
-  uint8_t byte0 = crc32c;
-  uint8_t byte1 = crc32c >> 8;
-  uint8_t byte2 = crc32c >> 16;
-  uint8_t byte3 = crc32c >> 24;
-  crc32c = ((byte0 << 24) | (byte1 << 16) | (byte2 << 8) | byte3);
-  return crc32c;
+  absl::crc32c_t crc32 = absl::ComputeCrc32c(absl::string_view(
+      reinterpret_cast<const char*>(data.data()), data.size()));
+  return absl::byteswap(static_cast<uint32_t>(crc32));
 }
 }  // namespace dcsctp