Selectable: Added ImGuiSelectableFlags_AllowItemOverlap flag in public api (was previously internal only).

docs/CHANGELOG.txt

@@ -59,6 +59,7 @@ Other Changes:
   and then we will be able to make this the default.)
 - TreeNode: Added ImGuiTreeNodeFlags_SpanFullWidth flag. This extends the hit-box to both the left-most and
   right-most edge of the working area, bypassing indentation.
+- Selectable: Added ImGuiSelectableFlags_AllowItemOverlap flag in public api (was previously internal only).
 - Style: Allow style.WindowMenuButtonPosition to be set to ImGuiDir_None to hide the collapse button. (#2634, #2639)
 - Font: Better ellipsis drawing implementation. Instead of drawing three pixel-ey dots (which was glaringly
   unfitting with many types of fonts) we first attempt to find a standard ellipsis glyphs within the loaded set.

imgui.h

@@ -810,7 +810,8 @@ enum ImGuiSelectableFlags_
     ImGuiSelectableFlags_DontClosePopups    = 1 << 0,   // Clicking this don't close parent popup window
     ImGuiSelectableFlags_SpanAllColumns     = 1 << 1,   // Selectable frame can span all columns (text will still fit in current column)
     ImGuiSelectableFlags_AllowDoubleClick   = 1 << 2,   // Generate press events on double clicks too
-    ImGuiSelectableFlags_Disabled           = 1 << 3    // Cannot be selected, display grayed out text
+    ImGuiSelectableFlags_Disabled           = 1 << 3,   // Cannot be selected, display grayed out text
+    ImGuiSelectableFlags_AllowItemOverlap   = 1 << 4    // (WIP) Hit testing to allow subsequent widgets to overlap this one
 };
 
 // Flags for ImGui::BeginCombo()

imgui_internal.h

@@ -361,9 +361,8 @@ enum ImGuiSelectableFlagsPrivate_
     ImGuiSelectableFlags_PressedOnClick     = 1 << 21,
     ImGuiSelectableFlags_PressedOnRelease   = 1 << 22,
     ImGuiSelectableFlags_DrawFillAvailWidth = 1 << 23,  // FIXME: We may be able to remove this (added in 6251d379 for menus)
-    ImGuiSelectableFlags_AllowItemOverlap   = 1 << 24,
-    ImGuiSelectableFlags_DrawHoveredWhenHeld= 1 << 25,  // Always show active when held, even is not hovered. This concept could probably be renamed/formalized somehow.
-    ImGuiSelectableFlags_SetNavIdOnHover    = 1 << 26
+    ImGuiSelectableFlags_DrawHoveredWhenHeld= 1 << 24,  // Always show active when held, even is not hovered. This concept could probably be renamed/formalized somehow.
+    ImGuiSelectableFlags_SetNavIdOnHover    = 1 << 25
 };
 
 // Extend ImGuiTreeNodeFlags_