credocument: update getTextFromXPointers wrapper to support selections

With the latest koreader-base update, we can now create native
selections using getTextFromXPointers. In order to make the wrapper less
annoying to use, always enable segmented selection if selections are
enabled (to match getTextFromPositions).

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>

frontend/document/credocument.lua

@@ -828,8 +828,9 @@ function CreDocument:getTextFromXPointer(xp)
     end
 end
 
-function CreDocument:getTextFromXPointers(pos0, pos1)
-    return self._document:getTextFromXPointers(pos0, pos1)
+function CreDocument:getTextFromXPointers(pos0, pos1, draw_selection)
+    local draw_segmented_selection = draw_selection -- always use segmented selections
+    return self._document:getTextFromXPointers(pos0, pos1, draw_selection, draw_segmented_selection)
 end
 
 function CreDocument:getHTMLFromXPointer(xp, flags, from_final_parent)
@@ -1583,6 +1584,7 @@ function CreDocument:setupCallCache()
             elseif name == "highlightXPointer" then add_buffer_trash = true
             elseif name == "getWordFromPosition" then add_buffer_trash = true
             elseif name == "getTextFromPositions" then add_buffer_trash = true
+            elseif name == "getTextFromXPointers" then add_buffer_trash = true
             elseif name == "findText" then add_buffer_trash = true
             elseif name == "resetBufferCache" then add_buffer_trash = true
 
@@ -1611,7 +1613,6 @@ function CreDocument:setupCallCache()
             elseif name == "getHTMLFromXPointers" then no_wrap = true
             elseif name == "getImageFromPosition" then no_wrap = true
             elseif name == "getTextFromXPointer" then no_wrap = true
-            elseif name == "getTextFromXPointers" then no_wrap = true
             elseif name == "getPageOffsetX" then no_wrap = true
             elseif name == "getNextVisibleWordStart" then no_wrap = true
             elseif name == "getNextVisibleWordEnd" then no_wrap = true