Revert "Fix language tests wrt. warnings."

tests/language/double_to_string_as_exponential2_test.dart

Index: tests/language/double_to_string_as_exponential2_test.dart
diff --git a/tests/language/double_to_string_as_exponential2_test.dart b/tests/language/double_to_string_as_exponential2_test.dart
index e29676227907675dc1e81b7bfb9c0f8aeb6222fc..f5030ca70bc545764890b171c83c4ac16f23cd83 100644
--- a/tests/language/double_to_string_as_exponential2_test.dart
+++ b/tests/language/double_to_string_as_exponential2_test.dart
@@ -6,15 +6,14 @@
 import "package:expect/expect.dart";
 
 main() {
-  var v = 1.0;
-  Expect.throws(() => v.toStringAsExponential(-1),
+  Expect.throws(() => (1.0).toStringAsExponential(-1),
                 (e) => e is RangeError);
-  Expect.throws(() => v.toStringAsExponential(21),
+  Expect.throws(() => (1.0).toStringAsExponential(21),
                 (e) => e is RangeError);
-  Expect.throws(() => v.toStringAsExponential(1.5),
+  Expect.throws(() => (1.0).toStringAsExponential(1.5),
                 (e) => e is ArgumentError || e is TypeError);
-  Expect.throws(() => v.toStringAsExponential("string"),
+  Expect.throws(() => (1.0).toStringAsExponential("string"),
                 (e) => e is ArgumentError || e is TypeError);
-  Expect.throws(() => v.toStringAsExponential("3"),
+  Expect.throws(() => (1.0).toStringAsExponential("3"),
                 (e) => e is ArgumentError || e is TypeError);
 }