Revert 151879 "Remove virtual from functions that are never over..."

Broke two Chromium tests

BUG=247325

> Remove virtual from functions that are never overridden.
> 
> I checked these by writing a quick Python script; none of these functions
> are found in any other header files in this directory.
> 
> I was surprised how much this cuts down on code size. I'm going to
> aggressively get rid of virtual functions when they're not useful.
> The main reason this helps so much is because there are so many subclasses
> of AccessibilityObject.
> 
> BUG=247082
> 
> Review URL: https://chromiumcodereview.appspot.com/16465002

TBR=dmazzoni@chromium.org

Review URL: https://codereview.chromium.org/16147007

git-svn-id: svn://svn.chromium.org/blink/trunk@151938 bbb929c8-8fbe-4397-9dbb-9b2b20218538
2 files changed