Fix C4702 issues (unreachable code) in ANGLE, excluding <xtree>

Change-Id: Ia7603139af266fd7b14efc8c3465225738456e67
Reviewed-on: https://chromium-review.googlesource.com/261038
Tested-by: Austin Kinross <aukinros@microsoft.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/compiler/preprocessor/ExpressionParser.y b/src/compiler/preprocessor/ExpressionParser.y
index ea638ec..8caf36b 100644
--- a/src/compiler/preprocessor/ExpressionParser.y
+++ b/src/compiler/preprocessor/ExpressionParser.y
@@ -28,7 +28,7 @@
 #pragma GCC diagnostic ignored "-Wuninitialized"
 #endif
 #elif defined(_MSC_VER)
-#pragma warning(disable: 4065 4701)
+#pragma warning(disable: 4065 4701 4702)
 #endif
 
 #include "ExpressionParser.h"