Fix BUCK

Summary:
- Deleted a non-existent include
- Fix #404

Reviewed By: bolinfest

Differential Revision: D4569377

fbshipit-source-id: 34161b28be8bab476b30442596314899463814ef

YOGA_DEFS

@@ -1,7 +1,3 @@
-with allow_unsafe_import():
-  import os.path
-def isdir(filename):
-  return os.path.isdir(filename)
 
 YOGA_ROOT = '//...'
 JAVA_TARGET = '//java:java'
@@ -39,3 +35,8 @@ BASE_COMPILER_FLAGS = [
 
 def yoga_dep(dep):
   return '//' + dep
+
+with allow_unsafe_import():
+  import os.path
+def isdir(filename):
+  return os.path.isdir(filename)

csharp/BUCK

@@ -6,7 +6,6 @@
 # of patent rights can be found in the PATENTS file in the same directory.
 
 include_defs('//YOGA_DEFS')
-include_defs('xplat//configurations/buck/py_sdk')
 
 COMPILER_FLAGS = BASE_COMPILER_FLAGS + ['-std=c++11']