See the original report in https://github.com/facebook/react/issues/10772#issuecomment-333242375.

The problem is that SVG is case sensitive, and so naïvely setting `tabIndex` and relying on insensitivity won't work with it.

The good news is it seems like `tabindex` is the only valid [SVG attribute](https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute) with this problem. We just missed it because it applies both to HTML and SVG.

I think the fix is to add it back to the whitelist. 
type="checkbox"
              defaultChecked={false}
              checked={true}
              readOnly={true}
            />,
            1,
          );
          expect(e.checked).toBe(true);
          expect(e.getAttribute('defaultChecked')).toBe(null);
        },
      );
    });
    describe('textareas', function() {
      
      
      itRenders('a textarea with a value and an onChange', async render => {
        const e = await render(<textarea value="foo" onChange={() => {}} />);
        
        
        expect(e.getAttribute('value')).toBe(null);
        expect(e.value).toBe('foo');
      });
      itRenders('a textarea with a value and readOnly', async render => {
        const e = await render(<textarea value="foo" readOnly={true} />);
        
        
        expect(e.getAttribute('value')).toBe(null);
        expect(e.value).toBe('foo');
      });
      itRenders(