Property tree code must account for parent offsets of fixed layers

Property tree code must account for parent offsets of fixed layers

Even though fixed position layers are constrained to keep a constant
position wrt to their "fixed container," their initial position must
account for the position of layers between them and this container.

BUG=386810
Committed: https://crrev.com/0120eb267caade2d568b3b7fd4a02409a2150438
Cr-Commit-Position: refs/heads/master@{#318640}

[Ian Vollick, 2015-03-02 00:48:47]

vollick@chromium.org changed reviewers:
+ enne@chromium.org

[enne (OOO), 2015-03-02 01:12:26]

https://codereview.chromium.org/967163002/diff/20001/cc/trees/layer_tree_host...
File cc/trees/layer_tree_host_common_unittest.cc (right):

https://codereview.chromium.org/967163002/diff/20001/cc/trees/layer_tree_host...
cc/trees/layer_tree_host_common_unittest.cc:8847: // Property tree verification
will fail if position of child is not accounted
Verification will not persist in the future.  Maybe check draw transforms
explicitly?

https://codereview.chromium.org/967163002/diff/20001/cc/trees/property_tree_b...
File cc/trees/property_tree_builder.cc (right):

https://codereview.chromium.org/967163002/diff/20001/cc/trees/property_tree_b...
cc/trees/property_tree_builder.cc:144: } else if
(data_from_ancestor.transform_tree_parent !=
Aha!!

[Ian Vollick, 2015-03-02 01:28:00]

https://codereview.chromium.org/967163002/diff/20001/cc/trees/layer_tree_host...
File cc/trees/layer_tree_host_common_unittest.cc (right):

https://codereview.chromium.org/967163002/diff/20001/cc/trees/layer_tree_host...
cc/trees/layer_tree_host_common_unittest.cc:8847: // Property tree verification
will fail if position of child is not accounted
On 2015/03/02 01:12:26, enne wrote:
> Verification will not persist in the future.  Maybe check draw transforms
> explicitly?

Great point -- if we were to switch to property trees, this test would silently
test nothing. I've switched it to test the visible content rect from property
trees directly. Once we switch to property trees for real, this could will
obviously need to be updated when Layer::visible_rect_from_property_trees is
deleted.

[enne (OOO), 2015-03-02 02:22:10]

The CQ bit was checked by enne@chromium.org

[enne (OOO), 2015-03-02 02:22:10]

lgtm

[commit-bot: I haz the power, 2015-03-02 02:22:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/967163002/40001

[commit-bot: I haz the power, 2015-03-02 03:07:42]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-03-02 03:08:15]

Patchset 3 (id:??) landed as
https://crrev.com/0120eb267caade2d568b3b7fd4a02409a2150438
Cr-Commit-Position: refs/heads/master@{#318640}