Inputs: added wip/internal Input Owner system. (#456, #2637, #2620, #…

…2891, #3370, #4828, #5108, #5242, #5641)

- Added SetKeyOwner(), SetItemKeyOwner(), TestKeyOwner().
- Added new IsKeyXXX IsMouseXXX functions with ImGuID owner_id and flags.
- Obsoleted SetItemUsingMouseWheel(). (#2891)
- Removed IsKeyPresseedEx() which was a recent internal addition 2022-07-08 deemed to be temporary exactly for this.
- Added ImGuiButtonFlags_NoSetKeyOwner, ImGuiButtonFlags_NoTestKeyOwner
- Added ImGuiSelectableFlags_NoSetKeyOwner.
- Added ImGuiInputFlags_LockThisFrame, ImGuiInputFlags_LockUntilRelease for for SetKeyOwner(), SetItemKeyOwner().
- Added ImGuiInputFlags_CondXXX values for SetItemKeyOwner().

docs/CHANGELOG.txt

@@ -107,6 +107,17 @@ Other Changes:
 - Popups & Modals: fixed nested Begin() being erroneously input-inhibited. While it is
   unusual, you can nest a Begin() inside a popup or modal, it is occasionally useful to
   achieve certains things (e.g. some ways to implement suggestion popup #718, #4461).
+- Inputs: Standard widgets now claim for key/button ownership and test for them.
+  - Fixes scenario where e.g. a Popup with a Selectable() reacting on mouse down
+    (e.g. double click) closes, and behind it is another window with an item reacting
+    on mouse up. Previously this would lead to both items reacting, now the item in the
+    window behind won't react on the mouse up since the mouse button ownership has already
+    been claimed earlier.
+  - Internals: There are MANY more aspects to this changes. Added experimental/internal APIs
+    to allow handling input/shorting routing and key ownership. Things will be moved into
+    public APIs over time. For now this release is a way to test the solidity of underlying
+    systems while letting early adopters adopters toy with internals.
+    (#456, #2637, #2620, #2891, #3370, #3724, #4828, #5108, #5242, #5641)
 - Scrolling: Tweak mouse-wheel locked window timer so it is shorter but also gets reset
   whenever scrolling again (#2604).
 - Scrolling: Mitigated issue where multi-axis mouse-wheel inputs (usually from touch pad
@@ -116,7 +127,7 @@ Other Changes:
 - InputText: numerical fields automatically accept full-width characters (U+FF01..U+FF5E)
   by converting them to half-width (U+0021..U+007E).
 - InputText: added ImGuiInputTextFlags_EscapeClearsAll flag: first press on Escape clears
-  text if any, second press deactivate the InputText(). (#5688)
+  text if any, second press deactivate the InputText(). (#5688, #2620)
 - InputText: added support for shift+click style selection. (#5619) [@procedural]
 - InputText: clarified that callbacks cannot modify buffer when using the ReadOnly flag.
 - InputText: fixed minor one-frame selection glitch when reverting with Escape.