Patches for building the latest Abseil in the Flutter engine source tree

Change-Id: Ib3c9889be57dc97f5b8744f5bc7588464a040aa4
Reviewed-on: https://flutter-review.googlesource.com/c/third_party/abseil-cpp/+/32145
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Chinmay Garde <chinmaygarde@google.com>

BUILD.gn

diff --git a/BUILD.gn b/BUILD.gn
index d8b6501..b623246 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -7,7 +7,6 @@
 # without these options will be part of the same program.
 
 import("//build/config/c++/c++.gni")
-import("//build/config/nacl/config.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/toolchain/toolchain.gni")
 import("//build_overrides/build.gni")
@@ -121,6 +120,8 @@
 
 config("absl_include_config") {
   include_dirs = [ "." ]
+  cflags_cc = [ "-Wno-deprecated-builtins" ]
+  cflags_objcc = [ "-Wno-deprecated-builtins" ]
 }
 
 config("absl_define_config") {

absl/random/internal/BUILD.gn

diff --git a/absl/random/internal/BUILD.gn b/absl/random/internal/BUILD.gn
index d6a7736..df3d895 100644
--- a/absl/random/internal/BUILD.gn
+++ b/absl/random/internal/BUILD.gn
@@ -167,7 +167,6 @@
   ]
   sources = [ "randen_round_keys.cc" ]
   deps = [
-    "//build:chromeos_buildflags",
     "//third_party/abseil-cpp/absl/base:config",
   ]
 }