Add missing functions to SkNWayCanvas

Add missing functions to SkNWayCanvas

R=reed@google.com
BUG=none

Committed: http://code.google.com/p/skia/source/detail?r=12295

[enne (OOO), 2013-11-13 23:39:50]

This patch fixes the root cause of issue chromium:318782 that came up when I
landed https://codereview.chromium.org/63443003 that includes SkNWayCanvas use
when rastering.  

Although, according to issue 501 SkNWayCanvas is apparently not well supported
and might get removed?  Do you have a better suggestion of how to combine
analysis and rastering?

[enne (OOO), 2013-11-13 23:41:32]

https://codereview.chromium.org/65513003/diff/1/include/utils/SkNWayCanvas.h
File include/utils/SkNWayCanvas.h (right):

https://codereview.chromium.org/65513003/diff/1/include/utils/SkNWayCanvas.h#...
include/utils/SkNWayCanvas.h:41: virtual void clear(SkColor) SK_OVERRIDE;
This was the real fix.  The other functions were added just for completeness.

https://codereview.chromium.org/65513003/diff/1/include/utils/SkNWayCanvas.h#...
include/utils/SkNWayCanvas.h:45: virtual void drawRect(const SkRect&, const
SkPaint&) SK_OVERRIDE;
This is just a reordering to be consistent with SkCanvas's ordering.

[reed1, 2013-11-14 16:12:54]

lets land this now (thanks for the fix). We should also add a unittest to catch
this sort of thing in the future if we can. Lets at least file a bug to that
effect.

[Justin Novosad, 2013-11-14 16:16:36]

I am baffled to see bugs like this due to simple omissions (lack of
maintenance).  We clearly need to address the lack test coverage for
SkNWayCanvas, especially now that Chrome has a dependency on this dusty old
fella.

Mike, should we add an "Nway" pass to gm?

[reed1, 2013-11-14 16:26:38]

On 2013/11/14 16:16:36, junov wrote:
> I am baffled to see bugs like this due to simple omissions (lack of
> maintenance).  We clearly need to address the lack test coverage for
> SkNWayCanvas, especially now that Chrome has a dependency on this dusty old
> fella.
> 
> Mike, should we add an "Nway" pass to gm?

sgtm

[enne (OOO), 2013-11-14 18:11:14]

I think if you were willing to create a pure virtual SkCanvasInterface and made
derived classes implement interface instead of SkCanvas directly then that might
help you let the compiler tell you when you hadn't updated some derived class
with new functions.  It looks like there are a ton of SkCanvas-derived classes
in Skia and Chromium and I would not be surprised to see a whole class of this
sort of bug.

[commit-bot: I haz the power, 2013-11-14 18:11:22]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a lowly provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[reed1, 2013-11-14 18:34:43]

lgtm

[commit-bot: I haz the power, 2013-11-14 18:45:26]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/enne@chromium.org/65513003/1

[commit-bot: I haz the power, 2013-11-14 19:02:43]

Change committed as 12295