Remove virtual from functions that are never overridden

• Component: Accessibility
• Status: ASSIGNED ---

[Ryosuke Niwa]

Consider merging https://chromium.googlesource.com/chromium/blink/+/27ae848f12fb48ae823605c434b4a3ce96ac2c53

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.

I wonder if we have LLVM tool that finds unnecessary virtual for us?

[Ryosuke Niwa]

Reverted in https://chromium.googlesource.com/chromium/blink/+/c0729d4eddd4616daafcd15444961926d6e5f0c1.

[Ryosuke Niwa]

Relanded in https://chromium.googlesource.com/chromium/blink/+/2901a081b741106a34d2b3c0f848ea82b031dafd.

[chris fleizach]

Yea we should definitely do this, but I straight merge probably won't anymore now that they're pulling AX code out. We'll need to go through by hand and do this

[Ryosuke Niwa]

Also see https://chromium.googlesource.com/chromium/blink/+/c048c5c7c2578274d82faf96e9ebda4c55e428da

[Radar WebKit Bug Importer]

<rdar://problem/16014095>