Fix pointer to int conversion warning in EGLWindow.cpp

BUG=angleproject:892

Change-Id: If6f0eb13bca10f9328faeaab35665a67e7ef6e44
Reviewed-on: https://chromium-review.googlesource.com/269122
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>

util/EGLWindow.cpp

@@ -166,17 +166,12 @@ bool EGLWindow::initializeGL(OSWindow *osWindow)
     surfaceAttributes.push_back(EGL_NONE);
 
     mSurface = eglCreateWindowSurface(mDisplay, mConfig, osWindow->getNativeWindow(), &surfaceAttributes[0]);
-    if (mSurface == EGL_NO_SURFACE)
-    {
-        eglGetError(); // Clear error and try again
-        mSurface = eglCreateWindowSurface(mDisplay, mConfig, NULL, NULL);
-    }
-
     if (eglGetError() != EGL_SUCCESS)
     {
         destroyGL();
         return false;
     }
+    ASSERT(mSurface != EGL_NO_SURFACE);
 
     EGLint contextAttibutes[] =
     {