GN: Use gold linker for arm64

build/config/android/BUILD.gn

Index: build/config/android/BUILD.gn
diff --git a/build/config/android/BUILD.gn b/build/config/android/BUILD.gn
index f88f8ac7b4393621fc6cccea5307f3874e030513..67361fbd6d517393f0ae266514a81b353640a938 100644
--- a/build/config/android/BUILD.gn
+++ b/build/config/android/BUILD.gn
@@ -44,7 +44,8 @@ config("compiler") {
   }
 
   # Use gold for Android for most CPU architectures.
-  if (current_cpu == "x86" || current_cpu == "x64" || current_cpu == "arm") {
+  if (current_cpu == "x86" || current_cpu == "x64" || current_cpu == "arm" ||
+      current_cpu == "arm64") {
     ldflags += [ "-fuse-ld=gold" ]
     if (is_clang) {
       # Let clang find the ld.gold in the NDK.
@@ -167,6 +168,8 @@ config("runtime_library") {
     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.
+      # Passing via -l (as is done in libs) works only with gold, and not with
+      # the system linker.
       rebase_path(android_libgcc_file),
     ]
   }