Remove empty continuations in RenderObject::removeFromParentAndDestroyCleaningUpAnony...
authorantti@apple.com <antti@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Thu, 2 Nov 2017 11:31:06 +0000 (11:31 +0000)
committerantti@apple.com <antti@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Thu, 2 Nov 2017 11:31:06 +0000 (11:31 +0000)
commit412248b6893e44bf01dd2043296c3d8d3752983c
tree4fdba00a4897440f663335e7fc26efeea58f5486
parenta45c882c4e45b5655a92b74129a0cae558a962f2
Remove empty continuations in RenderObject::removeFromParentAndDestroyCleaningUpAnonymousWrappers
https://bugs.webkit.org/show_bug.cgi?id=179014

Reviewed by Geoff Garen.

Source/WebCore:

Treat continuation similarly to other anonymous wrappers. This makes things more understandable
and allows removal of some questionable code in RenderBlock::takeChild.

The patch also makes continuation chain a double linked so we can efficiently remove single
continuations from the chain. It also gets rid of algorithms that recurse in continuation chain.

* accessibility/AccessibilityRenderObject.cpp:
(WebCore::firstChildInContinuation):
* rendering/RenderBlock.cpp:
(WebCore::RenderBlock::styleDidChange):

    Don't add and remove continuations from the chain when updating style. Prevent recursion by walking
    the chain only in the (non-continuation) head renderer.

(WebCore::RenderBlock::dropAnonymousBoxChild):

    Make a member function.

(WebCore::RenderBlock::takeChild):

    Remove code that destroyed empty continuations and caused the parent to destroy itself.
    Empty continuations are now removed by RenderObject::removeFromParentAndDestroyCleaningUpAnonymousWrappers.

* rendering/RenderBlock.h:
* rendering/RenderBoxModelObject.cpp:
(WebCore::RenderBoxModelObject::ContinuationChainNode::ContinuationChainNode):
(WebCore::RenderBoxModelObject::ContinuationChainNode::~ContinuationChainNode):
(WebCore::RenderBoxModelObject::ContinuationChainNode::insertAfter):

    Track continuations with double linked lists.

(WebCore::continuationChainNodeMap):
(WebCore::RenderBoxModelObject::willBeDestroyed):

    Don't recurse to destroy continuation chain.
    Destroy all continuations iteratively if this is the head of the chain.
    When destroying a continuation renderer simply remove it from the chain.

(WebCore::RenderBoxModelObject::continuation const):
(WebCore::RenderBoxModelObject::insertIntoContinuationChainAfter):
(WebCore::RenderBoxModelObject::removeFromContinuationChain):
(WebCore::RenderBoxModelObject::ensureContinuationChainNode):
(WebCore::continuationMap): Deleted.
(WebCore::RenderBoxModelObject::setContinuation): Deleted.
* rendering/RenderBoxModelObject.h:
* rendering/RenderElement.cpp:
(WebCore::RenderElement::RenderElement):
(WebCore::RenderElement::removeAnonymousWrappersForInlinesIfNecessary):

    Make this a function of the parent renderer itself instead of getting 'parent()' as first operation and
    then using it.
    Don't remove continuations (isAnonymousBlockContinuation() test gives wrong result for the last continuation of the chain).

(WebCore::RenderElement::styleDidChange):

    removeAnonymousWrappersForInlinesIfNecessary is no function of the parent.

(WebCore::RenderElement::updateOutlineAutoAncestor):
* rendering/RenderElement.h:
(WebCore::RenderElement::hasContinuationChainNode const):
(WebCore::RenderElement::setHasContinuationChainNode):
(WebCore::RenderElement::hasContinuation const): Deleted.
(WebCore::RenderElement::setHasContinuation): Deleted.
* rendering/RenderInline.cpp:
(WebCore::RenderInline::styleDidChange):

    Don't add and remove continuations from the chain when updating style. Prevent recursion by walking
    the chain only in the (non-continuation) head renderer.

(WebCore::RenderInline::addChildIgnoringContinuation):

    Remove the old continuation from the chain. splitFlow() will add it back into the right place.

(WebCore::RenderInline::splitInlines):
(WebCore::RenderInline::addChildToContinuation):
(WebCore::RenderInline::childBecameNonInline):

    Remove the old continuation from the chain. splitFlow() will add it back into the right place.

* rendering/RenderInline.h:
* rendering/RenderObject.cpp:
(WebCore::RenderObject::propagateRepaintToParentWithOutlineAutoIfNeeded const):
(WebCore::RenderObject::outputRenderObject const):
(WebCore::findDestroyRootIncludingAnonymous):

    Allow anonymous continuations as destroy roots.

(WebCore::RenderObject::removeFromParentAndDestroyCleaningUpAnonymousWrappers):

    Removing a continuation may leave behind unnecessary anonymous sibling wrappers.
    Call removeAnonymousWrappersForInlinesIfNecessary() on parent after removal to get rid of them.
    If takeChild/removeAnonymousWrappersForInlinesIfNecessary leaves us with empty anonymous parent destroy that too.

* rendering/RenderRubyRun.cpp:
(WebCore::RenderRubyRun::takeChild):

    Similar to RenderBlock::takeChild, remove the code that would make the renderer destroy itself.
    Cleaning up RenderRubyRuns is now handled by removeFromParentAndDestroyCleaningUpAnonymousWrappers.

LayoutTests:

* fast/ruby/float-overhang-from-ruby-text-expected.txt:
* platform/mac/fast/ruby/rubyDOM-remove-rt1-expected.txt:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@224327 268f45cc-cd09-0410-ab3c-d52691b4dbfc
15 files changed:
LayoutTests/ChangeLog
LayoutTests/fast/ruby/float-overhang-from-ruby-text-expected.txt
LayoutTests/platform/mac/fast/ruby/rubyDOM-remove-rt1-expected.txt
Source/WebCore/ChangeLog
Source/WebCore/accessibility/AccessibilityRenderObject.cpp
Source/WebCore/rendering/RenderBlock.cpp
Source/WebCore/rendering/RenderBlock.h
Source/WebCore/rendering/RenderBoxModelObject.cpp
Source/WebCore/rendering/RenderBoxModelObject.h
Source/WebCore/rendering/RenderElement.cpp
Source/WebCore/rendering/RenderElement.h
Source/WebCore/rendering/RenderInline.cpp
Source/WebCore/rendering/RenderInline.h
Source/WebCore/rendering/RenderObject.cpp
Source/WebCore/rendering/RenderRubyRun.cpp