Add get_target_outputs function to GN

tools/gn/function_toolchain.cc

Index: tools/gn/function_toolchain.cc
diff --git a/tools/gn/function_toolchain.cc b/tools/gn/function_toolchain.cc
index 43d8cd720592a0bf80b0ccb6595677ca3b26fe6c..c930df2f90fa9a6ad5dec9cfb605c2fdba3713d5 100644
--- a/tools/gn/function_toolchain.cc
+++ b/tools/gn/function_toolchain.cc
@@ -119,7 +119,13 @@ Value RunToolchain(Scope* scope,
   if (!block_scope.CheckForUnusedVars(err))
     return Value();
 
-  scope->settings()->build_settings()->ItemDefined(toolchain.PassAs<Item>());
+  // Save this target for the file.
+  Scope::ItemVector* collector = scope->GetItemCollector();
+  if (!collector) {
+    *err = Err(function, "Can't define a toolchain in this context.");
+    return Value();
+  }
+  collector->push_back(new scoped_ptr<Item>(toolchain.PassAs<Item>()));
   return Value();
 }