Implement tracking of BUILD.gn files used to define target, toolchain or

tools/gn/function_get_target_outputs_unittest.cc

Index: tools/gn/function_get_target_outputs_unittest.cc
diff --git a/tools/gn/function_get_target_outputs_unittest.cc b/tools/gn/function_get_target_outputs_unittest.cc
index c947709a2ed4f7a17d03b12921bd2cbc0820dd22..3bff2386c4d17c1705c246ee9efdc0f23532191f 100644
--- a/tools/gn/function_get_target_outputs_unittest.cc
+++ b/tools/gn/function_get_target_outputs_unittest.cc
@@ -57,7 +57,7 @@ class GetTargetOutputsTest : public testing::Test {
 }  // namespace
 
 TEST_F(GetTargetOutputsTest, Copy) {
-  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
+  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"), {});
   action->set_output_type(Target::COPY_FILES);
   action->sources().push_back(SourceFile("//file.txt"));
   action->action_values().outputs() =
@@ -72,7 +72,7 @@ TEST_F(GetTargetOutputsTest, Copy) {
 }
 
 TEST_F(GetTargetOutputsTest, Action) {
-  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
+  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"), {});
   action->set_output_type(Target::ACTION);
   action->action_values().outputs() = SubstitutionList::MakeForTest(
       "//output1.txt",
@@ -87,7 +87,7 @@ TEST_F(GetTargetOutputsTest, Action) {
 }
 
 TEST_F(GetTargetOutputsTest, ActionForeach) {
-  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"));
+  Target* action = new Target(setup_.settings(), GetLabel("//foo/", "bar"), {});
   action->set_output_type(Target::ACTION_FOREACH);
   action->sources().push_back(SourceFile("//file.txt"));
   action->action_values().outputs() = SubstitutionList::MakeForTest(