Resizer and etc attributes on table editor still use nsIDOMElement. Converting to Element makes both implementation and the callers simpler.
MozReview-Commit-ID: TTFSvqn5GE
In our coding rules, variable names of nsresult should be rv. Indeed, when you see |rv| in the code, you must assume that its type if nsresult.
However, a lot of code under editor/ uses |res| for the variables of nsresult. Let's replace |res| with |rv|.
And this patch improves following points:
1. When |rv| is set in both |if| and |else| block and they are check outside of them, this moves the check into each |if| and |else| block because even if the failure is notified with warning, you cannot see which case was performed and failed. This change makes it clear.
2. When |return rv;| returns non-error code because |rv| is checked with NS_ENSURE_SUCCESS() immediately before, setting replacing it with |return NS_OK;| is clearer.
3. Move declaration of |nsresult rv| into smaller scope as far as possible. This prevents setting rv to unexpected value and easier to check its value at reading the code.
MozReview-Commit-ID: 9MAqj7sFey3
