[deps] Update absl to 20250512.1 (grpc#39571)

Update absl dependency to https://github.com/abseil/abseil-cpp/releases/tag/20250512.1

As part of this upgrade, remove gRPC's usage of internal absl helper functions.
A similar fix is needed for OpenCensus-Cpp, but since that repo is archived, I am choosing to add in a patch. The aim is to delete our OpenCensus plugin so that we don't have to maintain this forever as per grpc/proposal#496.

Closes grpc#39571

PiperOrigin-RevId: 777770232

Author: yashykt

BUILD

@@ -2816,8 +2816,8 @@ grpc_cc_library(
     ],
     external_deps = [
         "absl/base:core_headers",
-        "absl/base:endian",
         "absl/log:check",
+        "absl/numeric:bits",
         "absl/status",
         "absl/status:statusor",
         "absl/strings",

CMakeLists.txt

@@ -22,15 +22,15 @@ module(
 # Regular dependencies
 # ====================
 
-bazel_dep(name = "abseil-cpp", version = "20250127.1", repo_name = "com_google_absl")
+bazel_dep(name = "abseil-cpp", version = "20250512.1", repo_name = "com_google_absl")
 bazel_dep(name = "apple_support", version = "1.17.1", repo_name = "build_bazel_apple_support")
 bazel_dep(name = "bazel_skylib", version = "1.7.1")
 bazel_dep(name = "boringssl", version = "0.20241024.0")  # mistmatched 20241211
 bazel_dep(name = "c-ares", version = "1.19.1", repo_name = "com_github_cares_cares")
 bazel_dep(name = "envoy_api", version = "0.0.0-20250128-4de3c74")
 bazel_dep(name = "googleapis", version = "0.0.0-20240819-fe8ba054a", repo_name = "com_google_googleapis")
 bazel_dep(name = "googletest", version = "1.16.0", repo_name = "com_google_googletest")
-bazel_dep(name = "opencensus-cpp", version = "0.0.0-20230502-50eb5de", repo_name = "io_opencensus_cpp")
+bazel_dep(name = "opencensus-cpp", version = "0.0.0-20230502-50eb5de.bcr.2", repo_name = "io_opencensus_cpp")
 bazel_dep(name = "openssl", version = "3.3.1.bcr.1")
 bazel_dep(name = "opentelemetry-cpp", version = "1.19.0", repo_name = "io_opentelemetry_cpp")
 bazel_dep(name = "platforms", version = "0.0.10")

MODULE.bazel

@@ -151,11 +151,11 @@ def grpc_deps():
     if "com_google_absl" not in native.existing_rules():
         http_archive(
             name = "com_google_absl",
-            sha256 = "b396401fd29e2e679cace77867481d388c807671dc2acc602a0259eeb79b7811",
-            strip_prefix = "abseil-cpp-20250127.1",
+            sha256 = "9b7a064305e9fd94d124ffa6cc358592eb42b5da588fb4e07d09254aa40086db",
+            strip_prefix = "abseil-cpp-20250512.1",
             urls = [
-                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/abseil/abseil-cpp/releases/download/20250127.1/abseil-cpp-20250127.1.tar.gz",
-                "https://github.com/abseil/abseil-cpp/releases/download/20250127.1/abseil-cpp-20250127.1.tar.gz",
+                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/abseil/abseil-cpp/archive/refs/tags/20250512.1.tar.gz",
+                "https://github.com/abseil/abseil-cpp/archive/refs/tags/20250512.1.tar.gz",
             ],
             repo_mapping = {
                 "@googletest": "@com_google_googletest",
@@ -204,6 +204,10 @@ def grpc_deps():
                 "https://storage.googleapis.com/grpc-bazel-mirror/github.com/census-instrumentation/opencensus-cpp/archive/5501a1a255805e0be83a41348bb5f2630d5ed6b3.tar.gz",
                 "https://github.com/census-instrumentation/opencensus-cpp/archive/5501a1a255805e0be83a41348bb5f2630d5ed6b3.tar.gz",
             ],
+            patches = [
+                "@com_github_grpc_grpc//third_party:opencensus-cpp.patch",
+            ],
+            patch_args = ["-p1"],
         )
 
     if "envoy_api" not in native.existing_rules():

Makefile

@@ -127,7 +127,7 @@ configs:
     CXX: clang++
     DEFINES: NDEBUG GRPC_UBSAN
     LD: clang++
-    LDFLAGS: -stdlib=libc++ -fsanitize=undefined,unsigned-integer-overflow
+    LDFLAGS: -stdlib=libc++ -fsanitize=undefined
     LDXX: clang++
     compile_the_world: true
     test_environ: