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/tests/end2end_tests/BufferDataTest.cpp b/src/tests/end2end_tests/BufferDataTest.cpp
index 5dcf29f..7f47935 100644
--- a/src/tests/end2end_tests/BufferDataTest.cpp
+++ b/src/tests/end2end_tests/BufferDataTest.cpp
@@ -362,7 +362,7 @@
     uint8_t srcBytes[numBytes];
     for (size_t i = 0; i < numBytes; ++i)
     {
-        srcBytes[i] = static_cast<uint8_t>(i);
+        srcBytes[i] = i;
     }
 
     void *dest = glMapBufferRange(GL_ARRAY_BUFFER, 0, numBytes, GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT);