add render mode to hint page

frontend/document/document.lua

@@ -203,8 +203,8 @@ end
 
 -- a hint for the cache engine to paint a full page to the cache
 -- TODO: this should trigger a background operation
-function Document:hintPage(pageno, zoom, rotation)
+function Document:hintPage(pageno, zoom, rotation, render_mode)
-	self:renderPage(pageno, nil, zoom, rotation)
+	self:renderPage(pageno, nil, zoom, rotation, render_mode)
 end
 
 --[[

frontend/ui/reader/readerview.lua

@@ -164,7 +164,7 @@ function ReaderView:onRotationUpdate(rotation)
 end
 
 function ReaderView:onHintPage()
-	self.ui.document:hintPage(self.state.page+1, self.state.zoom, self.state.rotation)
+	self.ui.document:hintPage(self.state.page+1, self.state.zoom, self.state.rotation, self.render_mode)
 end
 
 function ReaderView:onCloseDocument()