Prevent overflow of width/height of layout overflow rectangle which can cause scroll bar to misfunction.

When a child element is positioned very far away the width/height of layout overflow rectangle may overflow. The patch detects such cases in RenderOverflow::addLayoutOverflow and shift the top/left edges of the rectangle to avoid overflow. 

BUG=267462

Review URL: https://chromiumcodereview.appspot.com/22799017

git-svn-id: svn://svn.chromium.org/blink/trunk@156567 bbb929c8-8fbe-4397-9dbb-9b2b20218538