Revert "Revert of implement readPixels and writePixels natively, w/o using the (deprecated) (https://codereview.chromium.org/199733016/)"

This reverts commit 9a90bd16dc6756395c422adf0f24560d033ed9ea.

BUG=skia:
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/211293002

git-svn-id: http://skia.googlecode.com/svn/trunk@13939 2bbb7eff-a529-9590-31e7-b0007b416f81
13 files changed