eliminate config param -- it was always self's config

eliminate config param -- it was always self's config

BUG=skia:
R=bsalomon@google.com

Committed: https://code.google.com/p/skia/source/detail?r=14303

[reed1, 2014-04-22 03:04:54]

this change both simplifies, and will enable us to deepCopy RGBA and BGRA. Today
we can only do one, because the "other" returns kUnknown_Config when we tried to
translate it back to the old bitmap::config world.

[reed1, 2014-04-22 17:48:36]

ptal

[bsalomon, 2014-04-22 17:52:28]

lgtm

[reed1, 2014-04-22 18:12:31]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2014-04-22 18:13:04]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/reed@google.com/246513002/1

[reed1, 2014-04-22 18:20:46]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2014-04-22 18:21:06]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/reed@google.com/246513002/20001

[reed1, 2014-04-22 18:21:16]

The CQ bit was unchecked by reed@google.com

[reed1, 2014-04-22 18:23:28]

Committed patchset #2 manually as r14303 (presubmit successful).

[bsalomon, 2014-04-23 14:51:42]

A revert of this CL has been created in
https://codereview.chromium.org/249373003/ by bsalomon@google.com.

The reason for reverting is: Causes some layout_test failures around texture
backed bitmaps. Test names and crash logs accessible via:
https://storage.googleapis.com/chromium-layout-test-archives/linux_layout/138...

.