All classes deriving from nsIFrame that did not have any subclasses themselves
(at the time of writing this patch) have been marked with `final`.
Some other Layout classes have also been made final, but this was opportunistic
while working on nsIFrame subclasses, and is definitely not exhaustive, further
patches welcome; refer to bug 1332680.
Advantages of marking a class final include:
- Allowing the compiler to devirtualize some method calls (i.e., calling
virtual functions directly instead of going through the vtable),
- Indicating that the class is not currently subclassed,
- Preventing subclassing without being aware that this would remove the
finalization benefits of the parent class.
`final` does not signify that these classes should *never* be subclassed, this
is left for developers to decide.
Differential Revision: https://phabricator.services.mozilla.com/D5020
--HG--
extra : moz-landing-system : lando
This patch was generated automatically by the "modeline.py" script, available
here: https://github.com/amccreight/moz-source-tools/blob/master/modeline.py
For every file that is modified in this patch, the changes are as follows:
(1) The patch changes the file to use the exact C++ mode lines from the
Mozilla coding style guide, available here:
https://developer.mozilla.org/en-US/docs/Mozilla/Developer_guide/Coding_Style#Mode_Line
(2) The patch deletes any blank lines between the mode line & the MPL
boilerplate comment.
(3) If the file previously had the mode lines and MPL boilerplate in a
single contiguous C++ comment, then the patch splits them into
separate C++ comments, to match the boilerplate in the coding style.
MozReview-Commit-ID: EuRsDue63tK
--HG--
extra : rebase_source : 3356d4b80ff6213935192e87cdbc9103fec6084c
nsIFrame::mClass is of type enum class nsQueryFrame::ClassID which is
a strict subset of the nsQueryFrame::FrameIID values. For a concrete
frame class, its FrameIID is the same numeric value as its ClassID.
MozReview-Commit-ID: 1N0AkCGo1ol