In cimport_from_pyx mode don't treat "cdef extern from" variables as being...

In cimport_from_pyx mode don't treat "cdef extern from" variables as being defined, preventing erroneous cross-module cimport.

Cython/Compiler/Pipeline.py

@@ -275,6 +275,7 @@ def create_pyx_as_pxd_pipeline(context, result):
             break
     def fake_pxd(root):
         for entry in root.scope.entries.values():
+            if not entry.in_cinclude:
                 entry.defined_in_pxd = 1
         return StatListNode(root.pos, stats=[]), root.scope
     pipeline.append(fake_pxd)

tests/run/cimport_from_pyx.srctree

@@ -15,12 +15,13 @@ setup(
 
 ######## a.pyx ########
 
-from b cimport Bclass, Bfunc, Bstruct, Benum, Benum_value, Btypedef
+from b cimport Bclass, Bfunc, Bstruct, Benum, Benum_value, Btypedef, Py_EQ, Py_NE
 cdef Bclass b = Bclass(5)
 assert Bfunc(&b.value) == b.value
 assert b.asStruct().value == b.value
 cdef Btypedef b_type = &b.value
 cdef Benum b_enum = Benum_value
+cdef int tmp = Py_EQ
 
 #from c cimport ClassC
 #cdef ClassC c = ClassC()
@@ -28,6 +29,8 @@ cdef Benum b_enum = Benum_value
 
 ######## b.pyx ########
 
+from cpython.object cimport Py_EQ, Py_NE
+
 cdef enum Benum:
     Benum_value