Chrome Version: 68.0.3426.0
OS: Linux, but likely all desktop platforms

What steps will reproduce the problem?
(1) Navigate to https://www.irs.gov/pub/irs-pdf/fw4.pdf, or any other PDF that has forms text boxes.
(2) Click inside a form text box, type in "asdf".
(3) Use the mouse to select "asdf".
(4) Right click on the selection.

What is the expected result?

Context menu should appear.

What happens instead?

No context menu.


I bisected this to r555099. In RenderFrameImpl::ShowDeferredContextMenu(), |selection_text_| is empty and |params.selection_text| is not.