Rebuild GraphicsLayer tree when a LayoutPart's CDPLM configuration changes

Rebuild GraphicsLayer tree when a LayoutPart's CDPLM configuration changes

When a CompositedDeprecatedPaintLayerMapping's internal configuration
changes, the GraphicsLayer tree is rebuilt so that the CDPLM's
GraphicsLayers are reconnected to ancestors and descendants. However,
for CDPLMs owned by LayoutParts, the decision to rebuild ignores
whether the CDPLMs internal configuration has changed. This means that
after an internal configuration change (e.g., the removal of an ancestor
clipping layer), such a CDPLM's GraphicsLayers can be left disconnected
from the rest of the GraphicsLayer tree. This CL rebuilds the
GraphicsLayer tree when such a CDPLM's internal configuration changes.

BUG=497271
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197471

[ajuma, 2015-06-19 13:43:08]

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

[Ian Vollick, 2015-06-19 13:53:50]

On 2015/06/19 at 13:52:48, ajuma wrote:
> 

lgtm

[ajuma, 2015-06-19 13:56:57]

The CQ bit was checked by ajuma@chromium.org

[commit-bot: I haz the power, 2015-06-19 13:57:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1181743003/40001

[commit-bot: I haz the power, 2015-06-19 14:00:48]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197471