* SConstruct: Restore finding apr on the Windows buildbot. Broken since r1833230.

git-svn-id: https://svn.apache.org/repos/asf/serf/trunk@1866470 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/SConstruct b/SConstruct
index 9d0fc91..f4f1208 100644
--- a/SConstruct
+++ b/SConstruct
@@ -390,7 +390,8 @@
 
   if not env.get('SOURCE_LAYOUT', None):
     env.Append(LIBPATH=['$APR/lib', '$APU/lib'],
-               CPPPATH=['$APR/include', '$APU/include'])
+               CPPPATH=['$APR/include', '$APR/include/apr-1',
+                        '$APU/include', '$APU/include/apr-1'])
   elif aprstatic:
     env.Append(LIBPATH=['$APR/LibR','$APU/LibR'],
                CPPPATH=['$APR/include', '$APU/include'])