Bug 1833855 [Linux] Update GtkCompositorWidget to work on X11 only builds r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D178643

widget/gtk/GtkCompositorWidget.cpp

@@ -132,14 +132,14 @@ EGLNativeWindowType GtkCompositorWidget::GetEGLNativeWindow() {
   return window;
 }
 
-#if defined(MOZ_WAYLAND)
 void GtkCompositorWidget::SetEGLNativeWindowSize(
     const LayoutDeviceIntSize& aEGLWindowSize) {
+#if defined(MOZ_WAYLAND)
   if (mWidget) {
     mWidget->SetEGLNativeWindowSize(aEGLWindowSize);
   }
-}
 #endif
+}
 
 LayoutDeviceIntRegion GtkCompositorWidget::GetTransparentRegion() {
   // We need to clear target buffer alpha values of popup windows as

widget/gtk/GtkCompositorWidget.h

@@ -79,11 +79,12 @@ class GtkCompositorWidget : public CompositorWidget,
   // Resume rendering with to given aXWindow (X11) or nsWindow (Wayland).
   void EnableRendering(const uintptr_t aXWindow, const bool aShaped) override;
 
+  void SetEGLNativeWindowSize(const LayoutDeviceIntSize& aEGLWindowSize);
+
 #if defined(MOZ_X11)
   Window XWindow() const { return mXWindow; }
 #endif
 #if defined(MOZ_WAYLAND)
-  void SetEGLNativeWindowSize(const LayoutDeviceIntSize& aEGLWindowSize);
   RefPtr<mozilla::layers::NativeLayerRoot> GetNativeLayerRoot() override;
 #endif