cc: Create a Region class that wraps SkRegion, to replace use of WebCore::Region.

cc: Create a Region class that wraps SkRegion, to replace use of WebCore::Region.

We create a class in cc/ called Region which provides a gfx:: type-friendly API
to SkRegion, and allows for easily swapping out region implementations in the
future if required.

During the process, I removed tests dependency on a "size()" method on Region,
that used to give the number of rects in the Region's internal representation.
Instead, we always create a Region in the tests from our expected rects, and
compare the Regions directly. We use ToString() comparisons to get useful
failure outputs, similar to the unit tests of other geometry types in ui/gfx.

This uncovered a WTF::Vector holdout in the OcclusionTracker class, which is
converted to a std::vector.

Covered by existing tests; no change in behaviour.

R=enne
BUG=147395
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=166617

[danakj, 2012-11-05 21:09:56]

I moved the Deg2Rad etc mathods to math_util.h from geometry.h, seems a better
spot.

[danakj, 2012-11-05 21:13:30]

https://codereview.chromium.org/11366094/diff/3001/cc/math_util.cc
File cc/math_util.cc (right):

https://codereview.chromium.org/11366094/diff/3001/cc/math_util.cc#newcode12
cc/math_util.cc:12: #include "cc/geometry.h"
not needed now, will remove.

[enne (OOO), 2012-11-05 21:15:21]

https://codereview.chromium.org/11366094/diff/3001/cc/region.cc
File cc/region.cc (right):

https://codereview.chromium.org/11366094/diff/3001/cc/region.cc#newcode76
cc/region.cc:76: for (Iterator it(*this); it.has_rect(); it.next()) {
Is there any ordering constraint on the rects in region? In other words, if a
union a, b, c to and also union a, c, b, those should be logically identical,
but will the strings be the same?

[danakj, 2012-11-05 21:18:26]

https://codereview.chromium.org/11366094/diff/3001/cc/region.cc
File cc/region.cc (right):

https://codereview.chromium.org/11366094/diff/3001/cc/region.cc#newcode76
cc/region.cc:76: for (Iterator it(*this); it.has_rect(); it.next()) {
On 2012/11/05 21:15:21, enne wrote:
> Is there any ordering constraint on the rects in region? In other words, if a
> union a, b, c to and also union a, c, b, those should be logically identical,
> but will the strings be the same?

My expectation is that that regardless of the order you add the rects, you get
the same state inside the region.

I tried this in a unit test:
        EXPECT_EQ(UnionRegions(gfx::Rect(30, 30, 60, 10), gfx::Rect(30, 40, 70,
60)).ToString(), occlusion.occlusionInScreenSpace().ToString());
        EXPECT_EQ(UnionRegions(gfx::Rect(30, 40, 70, 60), gfx::Rect(30, 30, 60,
10)).ToString(), occlusion.occlusionInScreenSpace().ToString());

And it passed as expected.

[enne (OOO), 2012-11-05 21:18:43]

lgtm

[danakj, 2012-11-05 21:23:53]

Thanks! I had missed a change in the web_layer_impl, which, incidentally, wants
to use size().

Can you please double check this for me?

https://codereview.chromium.org/11366094/diff/5003/webkit/compositor_bindings...

[enne (OOO), 2012-11-05 21:30:11]

lgtm

[commit-bot: I haz the power, 2012-11-05 21:32:03]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11366094/5003

[commit-bot: I haz the power, 2012-11-05 22:19:03]

Sorry for I got bad news for ya.
Compile failed with a clobber build on win_rel.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...
Your code is likely broken or HEAD is junk. Please ensure your
code is not broken then alert the build sheriffs.
Look at the try server FAQ for more details.

[tfarina, 2012-11-07 00:18:03]

Dana have you abandoned this change?

[danakj, 2012-11-07 00:35:28]

On 2012/11/07 00:18:03, tfarina wrote:
> Dana have you abandoned this change?

No, I am waiting for skia to fix bugs in their region implementation. This will
fail the unit tests I've added currently.

[commit-bot: I haz the power, 2012-11-08 01:25:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11366094/4003

[commit-bot: I haz the power, 2012-11-08 01:37:00]

Sorry for I got bad news for ya.
Compile failed with a clobber build on android_dbg.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=android_db...
Your code is likely broken or HEAD is junk. Please ensure your
code is not broken then alert the build sheriffs.
Look at the try server FAQ for more details.

[commit-bot: I haz the power, 2012-11-08 01:40:42]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11366094/4003

[commit-bot: I haz the power, 2012-11-08 01:46:13]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11366094/7020

[commit-bot: I haz the power, 2012-11-08 06:26:55]

Change committed as 166617