Fix bug in scrollIntoView
Fix bug in scrollIntoView

Prior to this commit, if the vertical scroll bar is absent and the horizontal
scroll bar is present, a link to a particular point on the page which should
induce a horizontal scroll did not do so, because the absence of a vertical
scroll bar meant that the viewer was not recognized as the nearest scrolling
ancestor. This commit adds a check for horizontal scroll bars when searching
for the scrolling ancestor.

macroplant/pdf.js,Shoobx/pdf.js,Snuffleupagus/pdf.js,Shoobx/pdf.js,timvandermeij/pdf.js,xavier114fch/pdf.js,mukulmishra18/pdf.js,nawawi/pdf.js,Snuffleupagus/pdf.js,mozilla/pdf.js,macroplant/pdf.js,nawawi/pdf.js,mozilla/pdf.js,mukulmishra18/pdf.js,caremerge/pdf.js,Snuffleupagus/pdf.js,Shoobx/pdf.js,caremerge/pdf.js,mainegreen/pdf.js,timvandermeij/pdf.js,nawawi/pdf.js,showpad/mozilla-pdf.js,timvandermeij/pdf.js,showpad/mozilla-pdf.js,mozilla/pdf.js,mainegreen/pdf.js,showpad/mozilla-pdf.js,macroplant/pdf.js,xavier114fch/pdf.js