In render_pictures tiled rendering, draw a separate PNG for each tile.

Since the passed in picture may represent an image which is too large
to be represented on the GPU, never create such a large canvas. Instead,
after drawing to each tile, create a file showing just that tile.

Review URL: https://codereview.appspot.com/6532056

git-svn-id: http://skia.googlecode.com/svn/trunk@5603 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed