Fix 64-bit use of Win32Window.

An incorrect call to SetWindowLongPtr was crashing the 64-bit test.

BUG=angle:705

Change-Id: I3815bb0a1308f5e66e74faead37c0ae09f975a10
Reviewed-on: https://chromium-review.googlesource.com/214883
Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/util/win32/Win32Window.cpp b/util/win32/Win32Window.cpp
index 0f66d23..2b492ea 100644
--- a/util/win32/Win32Window.cpp
+++ b/util/win32/Win32Window.cpp
@@ -406,8 +406,6 @@
                                     sizeRect.right - sizeRect.left, sizeRect.bottom - sizeRect.top, NULL, NULL,
                                     GetModuleHandle(NULL), this);
 
-    SetWindowLongPtrA(mNativeWindow, GWLP_USERDATA, reinterpret_cast<LONG>(this));
-
     ShowWindow(mNativeWindow, SW_SHOW);
 
     mNativeDisplay = GetDC(mNativeWindow);