Cleanup SkPicture* classes a bit

Cleanup SkPicture* classes a bit


This is an attempt to reduce the number of friends the various SkPicture* classes have.
Probably the only controversial part is making getBitmap, getPath, getPicture and getPaint
public on SkPictureData (and adding a new initIterator entry point).

Committed: https://skia.googlesource.com/skia/+/6142609b22814283210f79d698182b651a93136c

[reed1, 2014-07-10 15:58:04]

api very-lgtm

[mtklein, 2014-07-10 15:59:51]

lgtm

Adding these public accessors to SkPictureData seems totally reasonable to me.

[robertphillips, 2014-07-10 16:22:45]

The CQ bit was checked by robertphillips@google.com

[commit-bot: I haz the power, 2014-07-10 16:22:59]

CQ is trying da patch. Follow status at

https://skia-tree-status.appspot.com/cq/robertphillips@google.com/384753004/2...

[commit-bot: I haz the power, 2014-07-10 16:35:17]

Change committed as 6142609b22814283210f79d698182b651a93136c