Fixup UTs for MSVC and Release Mode

Summary: This fixes incompatibility with MSVC in /W3 (designated initializers, precision loss) along with guarding tests which will only pass in DEBUG builds

Reviewed By: cortinico

Differential Revision: D42406531

fbshipit-source-id: 2c0d59678f76decf9b9b4d91a7c9ec12136ca1b9

tests/YGLoggerTest.cpp

@@ -9,6 +9,8 @@
 #include <stdarg.h>
 #include <yoga/Yoga.h>
 
+#if DEBUG
+
 namespace {
 char writeBuffer[4096];
 int _unmanagedLogger(
@@ -131,3 +133,5 @@ TEST(YogaTest, logger_node_with_children_should_print_indented) {
       "style=\"\" ></div>\n</div>";
   ASSERT_STREQ(expected, writeBuffer);
 }
+
+#endif