Revert GN declare_args() change.

tools/gn/functions_unittest.cc

Index: tools/gn/functions_unittest.cc
diff --git a/tools/gn/functions_unittest.cc b/tools/gn/functions_unittest.cc
index 949b844b34bc3a9b2ad5eafdd6653ad3802ccb35..7156747471225952ae48d78b3b5f4ca8e509449b 100644
--- a/tools/gn/functions_unittest.cc
+++ b/tools/gn/functions_unittest.cc
@@ -125,48 +125,3 @@ TEST(Functions, SplitList) {
       "rounding = [[1, 2], [3, 4], [5], [6]]\n",
       setup.print_output());
 }
-
-TEST(Functions, DeclareArgs) {
-  TestWithScope setup;
-  Err err;
-
-  // It is not legal to read the value of an argument declared in a
-  // declare_args() from inside the call, but outside the call and in
-  // a separate call should work.
-
-  TestParseInput reading_from_same_call(R"(
-      declare_args() {
-        foo = true
-        bar = foo
-      })");
-  reading_from_same_call.parsed()->Execute(setup.scope(), &err);
-  ASSERT_TRUE(err.has_error());
-
-  TestParseInput reading_from_outside_call(R"(
-      declare_args() {
-        foo = true
-      }
-
-      bar = foo
-      assert(bar)
-      )");
-  err = Err();
-  reading_from_outside_call.parsed()->Execute(setup.scope(), &err);
-  ASSERT_FALSE(err.has_error());
-
-  TestParseInput reading_from_different_call(R"(
-      declare_args() {
-        foo = true
-      }
-
-      declare_args() {
-        bar = foo
-      }
-
-      assert(bar)
-      )");
-  err = Err();
-  TestWithScope setup2;
-  reading_from_different_call.parsed()->Execute(setup2.scope(), &err);
-  ASSERT_FALSE(err.has_error());
-}