Remove the usage of some c++11 library features

That were causing compilation error in Chromium Mac builds

BUG=angleproject:891

Change-Id: I45777451b300928e8c8d232a5b7ecffa7f1c3cbe
Reviewed-on: https://chromium-review.googlesource.com/299721
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tryjob-Request: Corentin Wallez <cwallez@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/tests/gl_tests/UnpackAlignmentTest.cpp b/src/tests/gl_tests/UnpackAlignmentTest.cpp
index f9c31c1..5c49052 100644
--- a/src/tests/gl_tests/UnpackAlignmentTest.cpp
+++ b/src/tests/gl_tests/UnpackAlignmentTest.cpp
@@ -6,8 +6,6 @@
 
 #include "test_utils/ANGLETest.h"
 
-#include <array>
-
 using namespace angle;
 
 namespace
@@ -114,8 +112,8 @@
         glGetIntegerv(GL_UNPACK_ALIGNMENT, &readbackAlignment);
         EXPECT_EQ(alignment, readbackAlignment);
 
-        std::array<GLubyte, 1024> buf;
-        std::fill(buf.begin(), buf.end(), 0);
+        GLubyte buf[1024];
+        memset(buf, 0, sizeof(buf));
 
         unsigned int pixelSize;
         getPixelSize(format, type, &pixelSize);