* Fixup FindFrameForContentSibling to don't duplicate work and trigger assertions for display: contents
* Enable lazy frame construction for display: contents direct descendants
Tag #1375
* Implementation for assignedNodes
* Include slots in the flat tree
* Fix event get-the-parent algorithm for a node
* Update and add reftests for Shadow DOM v1
* Update web platform tests expectations
Tag #1375
* Cleanup a bit the ShadowRoot code
* Privatize ShadowRoot methods
* When the shadow tree distribution changes, post a restyle + reframe
* Simplify ShadowRoot::IsPooledNode
* Be a bit better at detecting distribution changes
Tag #1375
* Use inFlowFrame to check the target frame is summary and its parent is details
* Check summary frame instead of summary element on removing the summary
Tag #1375
* Stop calling SetHasDirAuto/ClearHasDirAuto in input element code
* Introduce event state flags that track the state of an element's dir attribute
* Rewrite our existing checks for the state of the dir attr on top of the new event state flags
* Add pseudo-classes for matching on the dir attribute states
* Use the new dir attribute pseudoclasses in html.css
Tag #1375
* Add a node property to access the ::before and ::after pseudo-elements
* Look for the frame for ::before and ::after pseudos
* Clean up pseudo-element props
* Simplify nsLayoutUtils callers, and make child iterators notice display: contents pseudos
Tag #1375
* Tidy RestyleManager::ContentStateChanged
* Convert UndisplayedMap to a typed hashtable
* Cleanup infallible or unchecked nsCSSFrameConstructor methods
Tag #1375
* Prevent canvas custom content from becoming NAC when reframing the root element
* Add an API to get computed style values through an AnonymousContent object
Tag #1375
* Stop using a node bit for HasExplicitBaseURI
* Move MAY_HAVE_CLASS to mBoolFlags
* Add a flag to indicate that a node is native anonymous content
* Allow tagging of pseudo-implementing native anonymous content with the pseudo type at creation time, and eliminate explicit style contexts in nsIAnonymousContentCreator::ContentInfo
Tag #1375
* Make StyleChildrenIterator skip NAC generated by root element primary frame ancestors.
* Add nsINode::GetFlattenedTreeParentNodeForStyle.
* Add iterator class to find all restyle roots.
NOTE: Parts 1, 2, and "4.2"
Tag #1375
IsSelectionEditable should check whether the focus node and anchor node
aren't null before trying to use them.
This also changes the initialization of selections' aOutIndex to the
last range in the selection as a fallback in case we don't add a range
later (in AddItem) which could also end up with a null selection
otherwise if the additional selection nodes are removed.
