Bug 77503

Summary: [meta] Element should be able to have multiple shadow roots.
Product: WebKit Reporter: Shinya Kawanaka <shinyak>
Component: DOMAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: dglazkov, dominicc, hayato, morrita, shinyak
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 77930, 77931, 77935, 77938, 78596, 79008, 79221, 79342, 79854    
Bug Blocks: 76433, 77499, 77595    
Attachments:
Description Flags
Patch none

Description Shinya Kawanaka 2012-01-31 19:53:52 PST
When inserting shadow root (A) into an element having another shadow root (B),

Host should have a link to (A),
and (A) should have a link to (B),
and (A) and (B) should have a link to the host.
Comment 1 Shinya Kawanaka 2012-01-31 23:41:33 PST
As a first step, we want to have just an ability to have multiple shadow root. In this step, we don't consider how elements having multiple shadow roots are rendered.

Note that some kinds of elements have shadow tree by own. We should decline to add shadow root in such elements.
Comment 2 Dimitri Glazkov (Google) 2012-02-01 09:14:45 PST
(In reply to comment #1)
> Note that some kinds of elements have shadow tree by own. We should decline to add shadow root in such elements.

Why? A large reason of introducing multiple shadow subtrees per element is to _allow_ overriding shadow DOM of an element with a "built-in" shadow subtree. Can you explain what pitfalls I am not seeing here?
Comment 3 Shinya Kawanaka 2012-02-01 17:18:45 PST
(In reply to comment #2)
> (In reply to comment #1)
> > Note that some kinds of elements have shadow tree by own. We should decline to add shadow root in such elements.
> 
> Why? A large reason of introducing multiple shadow subtrees per element is to _allow_ overriding shadow DOM of an element with a "built-in" shadow subtree. Can you explain what pitfalls I am not seeing here?

Ah... Sorry, I didn't understand the motivation of multiple shadow subtrees. I was afraid that a user breaks current input implementation...

OK. That being the case, I don't have any reason to prevent overriding "built-in" shadow subtree.
Comment 4 Shinya Kawanaka 2012-02-01 19:56:10 PST
Created attachment 125066 [details]
Patch
Comment 5 Hajime Morrita 2012-05-28 23:41:17 PDT
All subbugs are landed. closing.