InvisibleButton: Made public a small selection of ImGuiButtonFlags (previously in imgui_internal.h) and allowed to pass them to InvisibleButton().

imgui.cpp

@@ -4455,6 +4455,7 @@ bool ImGui::IsMouseDoubleClicked(ImGuiMouseButton button)
     return g.IO.MouseDoubleClicked[button];
 }
 
+// Return if a mouse click/drag went past the given threshold. Valid to call during the MouseReleased frame.
 // [Internal] This doesn't test if the button is pressed
 bool ImGui::IsMouseDragPastThreshold(ImGuiMouseButton button, float lock_threshold)
 {
@@ -7848,6 +7849,7 @@ void ImGui::EndPopup()
     g.WithinEndChild = false;
 }
 
+// Open a popup if mouse is released over the item
 bool ImGui::OpenPopupContextItem(const char* str_id, ImGuiPopupFlags popup_flags)
 {
     ImGuiWindow* window = GImGui->CurrentWindow;