Revert "Fix and enable warning C4244 (Conversion from 'type1' to 'type2', possible loss of data)"

Causing a build failure on Mac/Clang:

./Tokenizer.cpp:551:7: error: extra tokens at end of #else directive [-Werror,-Wextra-tokens]
#else if defined(_MSC_VER)

http://build.chromium.org/p/chromium.gpu.fyi/builders/GPU%20Mac%20Builder/builds/29136

This reverts commit 3b26e231d99154814eb428f75a67bbe7a21adadc.

Change-Id: I2d11ddcc18130d908fd2ec3d6f5ab890cfccd5e7
Reviewed-on: https://chromium-review.googlesource.com/264983
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/compiler/preprocessor/ExpressionParser.cpp b/src/compiler/preprocessor/ExpressionParser.cpp
index 4a90322..616f4d7 100644
--- a/src/compiler/preprocessor/ExpressionParser.cpp
+++ b/src/compiler/preprocessor/ExpressionParser.cpp
@@ -86,7 +86,7 @@
 #pragma GCC diagnostic ignored "-Wuninitialized"
 #endif
 #elif defined(_MSC_VER)
-#pragma warning(disable: 4065 4244 4701 4702)
+#pragma warning(disable: 4065 4701 4702)
 #endif
 
 #include "ExpressionParser.h"