Change DontCheck under-invalidation checking mode to CacheSkipper

Change DontCheck under-invalidation checking mode to CacheSkipper

We have some situation that under-invalidation is difficult to resolve.
Previously we just set DontCheck under-invalidation checking mode when
ENABLE(ASSERT) and ignore unmatched CacheDisplayItems. Now we have
strict checking for unmatched CachedDisplayItems so we need to skip
cache in all modes.

Might be one of the reasons of bug 497614.

BUG=497614
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197304

[Xianzhu, 2015-06-17 23:24:33]

wangxianzhu@chromium.org changed reviewers:
+ chrishtr@chromium.org, pdr@chromium.org

[chrishtr, 2015-06-17 23:27:22]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2015-06-17 23:27:23]

lgtm

[commit-bot: I haz the power, 2015-06-17 23:28:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1195513004/1

[Xianzhu, 2015-06-17 23:28:38]

The CQ bit was unchecked by wangxianzhu@chromium.org

[Xianzhu, 2015-06-17 23:30:15]

Just noticed a bug in LayoutObjectDrawingRecorder because we initialize cache
skipper after DrawingRecorder so initialization of m_canUseCachedDrawing is not
controlled by the cache skipper. Fixing it.

[Xianzhu, 2015-06-18 00:04:49]

On 2015/06/17 23:30:15, Xianzhu wrote:
> Just noticed a bug in LayoutObjectDrawingRecorder because we initialize cache
> skipper after DrawingRecorder so initialization of m_canUseCachedDrawing is
not
> controlled by the cache skipper. Fixing it.

Done. Ptal.

[chrishtr, 2015-06-18 00:15:41]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2015-06-18 00:15:41]

lgtm

[commit-bot: I haz the power, 2015-06-18 00:16:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1195513004/40001

[commit-bot: I haz the power, 2015-06-18 01:36:00]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197304