GN: Do not use forward_dependent_configs_from variable.

mojo/public/mojo_application.gni

Index: mojo/public/mojo_application.gni
diff --git a/mojo/public/mojo_application.gni b/mojo/public/mojo_application.gni
index 0dfcefaf71abaf9ab9f65bf7ec5f1535adc0c401..33d25d4db9ad671494fc42f7731cdaad235bb4bb 100644
--- a/mojo/public/mojo_application.gni
+++ b/mojo/public/mojo_application.gni
@@ -96,9 +96,6 @@ template("mojo_native_application") {
                          ".",
                          mojo_root)
       deps += mojo_deps
-      if (defined(invoker.forward_dependent_configs_from)) {
-        forward_dependent_configs_from = invoker.forward_dependent_configs_from
-      }
       if (defined(invoker.public_deps)) {
         public_deps = invoker.public_deps
       }
@@ -214,9 +211,6 @@ template("mojo_native_application") {
                          ".",
                          mojo_root)
       deps += mojo_deps
-      if (defined(invoker.forward_dependent_configs_from)) {
-        forward_dependent_configs_from = invoker.forward_dependent_configs_from
-      }
       if (defined(invoker.public_deps)) {
         public_deps = invoker.public_deps
       }