Add ifdef guard around gpu-specific code in native windows window.

Review URL: https://codereview.chromium.org/1405963014

AUTHORS

@@ -37,3 +37,4 @@ The Chromium Authors <*@chromium.org>
 Thiago Fransosi Farina <thiago.farina@gmail.com>
 Jose Mayol <jei.mayol@gmail.com>
 Linaro <*@linaro.org>
+Christian Plesner Hansen <plesner@t.undra.org>

src/views/win/SkOSWindow_win.cpp

@@ -692,9 +692,11 @@ bool SkOSWindow::makeFullscreen() {
     if (fFullscreen) {
         return true;
     }
+#if SK_SUPPORT_GPU
     if (fHGLRC) {
         this->detachGL();
     }
+#endif // SK_SUPPORT_GPU
     // This is hacked together from various sources on the web. It can certainly be improved and be
     // made more robust.