Re-enable passing tests

packages/unit/test/engine/paragraph_builder_test.dart

diff --git a/packages/unit/test/engine/paragraph_builder_test_disabled.dart b/packages/unit/test/engine/paragraph_builder_test.dart
similarity index 100%
rename from packages/unit/test/engine/paragraph_builder_test_disabled.dart
rename to packages/unit/test/engine/paragraph_builder_test.dart

packages/unit/test/engine/rect_test.dart

diff --git a/packages/unit/test/engine/rect_test_disabled.dart b/packages/unit/test/engine/rect_test.dart
similarity index 100%
rename from packages/unit/test/engine/rect_test_disabled.dart
rename to packages/unit/test/engine/rect_test.dart