idl_parser: Fix a typo in IDLNode

POSSITION -> POSITION.

No one uses this property so we may want to remove it, but I feel
that this is worth keeping for debugging etc.

Bug: None
Change-Id: I9625a4ee33917703a926f83febf38734a9579814
Reviewed-on: https://chromium-review.googlesource.com/644629
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#498770}

tools/idl_parser/idl_node.py

@@ -83,7 +83,7 @@ def __init__(self, cls, filename, lineno, pos, children=None):
       'WARNINGS': [],
       'FILENAME': filename,
       'LINENO' : lineno,
-      'POSSITION' : pos,
+      'POSITION' : pos,
     }
 
     self._children = []