GN(android): Default libs logic from runtime_library -> default_libs

build/config/android/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/sysroot.gni")
 
 assert(is_android)
 
@@ skipping 124 matching lines @@
         rebase_path("$android_libcpp_root/libcxx/include", root_build_dir),
     "-isystem" + rebase_path(
             "$android_ndk_root/sources/cxx-stl/llvm-libc++abi/libcxxabi/include",
             root_build_dir),
     "-isystem" +
         rebase_path("$android_ndk_root/sources/android/support/include",
                     root_build_dir),
   ]
 
   defines = [ "__GNU_SOURCE=1" ]  # Necessary for clone().
-  ldflags = [ "-nostdlib" ]
-  lib_dirs = [ "$android_libcpp_root/libs/$android_app_abi" ]
-
-  # The libc++ runtime library (must come first).
-  # ASan needs to dynamically link to libc++ even in static builds so
-  # that it can interpose operator new.
-  if (is_component_build || is_asan) {
-    libs = [ "c++_shared" ]
-  } else {
-    libs = [ "c++_static" ]
-  }
-
-  # libgcc must come before libdl for ld.bfd (MIPS)
-  if (current_cpu == "mipsel") {
-    libs += [
-      # ld linker is used for mips Android, and ld does not accept library
-      # absolute path prefixed by "-l"; Since libgcc does not exist in mips
-      # sysroot the proper library will be linked.
-      # TODO(gordanac): Remove once gold linker is used for mips Android.
-      "gcc",
-    ]
-  } else {
-    libs += [
-      # Manually link the libgcc.a that the cross compiler uses. This is
-      # absolute because the linker will look inside the sysroot if it's not.
-      rebase_path(android_libgcc_file),
-    ]
-  }
-
-  libs += [
-    "c",
-    "dl",
-    "m",
-  ]
 
   if (is_clang) {
     # Work around incompatibilities between bionic and clang headers.
     defines += [
       "__compiler_offsetof=__builtin_offsetof",
       "nan=__builtin_nan",
     ]
   }
 
   # TODO(jdduke) Re-enable on mips after resolving linking
   # issues with libc++ (crbug.com/456380).
   if (current_cpu != "mipsel" && current_cpu != "mips64el") {
-    ldflags += [ "-Wl,--warn-shared-textrel" ]
-  }
-
-  # Clang with libc++ does not require an explicit atomic library reference.
-  if (!is_clang) {
-    libs += [ "atomic" ]
+    ldflags = [ "-Wl,--warn-shared-textrel" ]
   }
 }
 
 config("executable_config") {
   cflags = [ "-fPIE" ]
   asmflags = [ "-fPIE" ]
   ldflags = [ "-pie" ]
 }
 
 config("hide_native_jni_exports") {
@@ skipping 29 matching lines @@
 
       # Avoid errors with current NDK:
       # "third_party/android_tools/ndk/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/include/arm_neon.h:3426:3: error: argument must be a constant"
       "-finstrument-functions-exclude-file-list=arm_neon.h",
     ]
   }
 }
 
 config("no_cygprofile_instrumentation") {
 }