--- a/widget/windows/moz.build
+++ b/widget/windows/moz.build
@@ -116,16 +116,17 @@ include('/ipc/chromium/chromium-config.m
 FINAL_LIBRARY = 'xul'
 
 if CONFIG['MOZ_ENABLE_SKIA_PDF']:
   LOCAL_INCLUDES += [
     '/gfx/skia/skia/include/config',
     '/gfx/skia/skia/include/core',
     '/modules/pdfium/pdfium/public',
   ]
+  TEST_DIRS += ['gtest']
 
 LOCAL_INCLUDES += [
     '/layout/generic',
     '/layout/xul',
     '/toolkit/xre',
     '/widget',
     '/widget/headless',
     '/xpcom/base',