Partition libcxx build code from build/config/sanitizers

build/config/BUILD.gn

Index: build/config/BUILD.gn
diff --git a/build/config/BUILD.gn b/build/config/BUILD.gn
index aff0e3d9d360a7248158fcf45a65fadcc479d7ac..882f18376bdd0b9c2aa066d1d6fa12d3b4df521b 100644
--- a/build/config/BUILD.gn
+++ b/build/config/BUILD.gn
@@ -264,13 +264,17 @@ config("default_libs") {
 }
 
 # Dependencies that all executables and shared libraries should have.
-# All targets that currently depend on //build/config/sanitizers:deps
-# are being made to depend on this target instead
-# (https://crbug.com/723069).
 group("exe_and_shlib_deps") {
-  public_deps = [
-    "//build/config/sanitizers:deps",
-  ]
+  public_deps = []
+  if (using_sanitizer) {
+    public_deps += [ "//build/config/sanitizers:deps" ]
+  }
+  if (use_custom_libcxx) {
+    public_deps += [ "//buildtools/third_party/libc++:libcxx_proxy" ]
+  }
+  if (use_afl) {
+    public_deps += [ "//third_party/afl" ]
+  }
 }
 
 # Executable configs -----------------------------------------------------------