Bug 1010470: Use :disabled pseudoclass instead of [disabled] attribute-selector to style disabled form controls on B2G & Android. r=fabrice

--HG--
rename : layout/reftests/forms/button/disabled-2.html => layout/reftests/forms/button/disabled-2a.html
rename : layout/reftests/forms/button/disabled-2.html => layout/reftests/forms/button/disabled-2b.html
Bug 1010621: Remove redundant definition for helper-function 'IsCompilingAsmJS'. r=djvj