[whatwg] Analogous DOM methods for the step attribute would be useful to have

[Brian Wilson]

There would be times when an author might want to provide a mega-stepping  
button for a field (for instance, when step is set closer to seconds,  
being able to change by day or year might be difficult to do by default on  
an input type=date field.) Plus, there have been a few tests that I've  
made recently where I wanted to force a step-up or step-down from the  
current value through script. Admittedly, that was a testing case so other  
use cases would be interesting to hear as well.

I'd propose two additional methods wherever the STEP attribute is legal:
    stepUp(n)
    stepDown(n)
Where n is an integer multiplier of the element's .step value - default  
value of n would be 1
All of the step attribute rules should apply to the resulting value (such  
as a resulting value exceeding the max, etc.)

-Brian

-- 
Brian Wilson
Opera Core QA