...and hook it up.
I opened MainMenu.xib in Xcode, added a new "Submenu Menu Item"
from the Library (cmd-shift-l), added a User Defined
"toggleShowClippingPaths:" action on First Responder and connected
the menu item's action to that action.
(I first tried duplicating the existing Window menu and editing that,
but the Window menu is marked as `systemMenu="window"` in the xib and
I couldn't find a way to undo that in Xcode. So the Debug menu first
acted as a second Window menu.)
I made "Debug" a toplevel menu to make it consistent with Ladybird.app
for now, but I'll probably make it a submenu of "View" in the future.
When the outline has focus, arrow keys navigate the outline instead
of changing the current page.
Add opt-up and opt-down as a way to move by one page even when the
outline has focus. (This matches Preview.app.)
xib change: Added two menu Previous Page with key equivalent opt-up
and Next Page with key equivalent opt-down to Go menu and bound them to
goToPreviousPage: and goToNextPage: on First Responder.
When the outline has focus, the responder chain is outline ->
window, so also add the actions on the window controller, and
let that forward to the PDF view.
This Just Works with NSToolbarSidebarTrackingSeparatorItemIdentifier,
as long as your window is has NSWindowStyleMaskFullSizeContentView
in its style mask. If it doesn't, things behave pretty weirdly and
at least in the docs I looked at, this requirement wasn't documented
at all :/
Anyways, switch MacPDFView to use safeAreaRect instead of bounds
now that we use NSWindowStyleMaskFullSizeContentView so that we
don't draw parts of the PDF under the title bar.
Also be careful to invalidate the PDF view if safeAreaRect changes,
so that the page is redrawn when toolbar visibility gets toggled.
