[PDF] Fix node count in page tree.

It should be the number of leaves below a given node, not the number of direct children in the node.

Review URL: http://codereview.appspot.com/4355044

git-svn-id: http://skia.googlecode.com/svn/trunk@1082 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed