addDirty method
Implementation
void addDirty(int delta) {
var wasDirty = dirtyWidgets > 0;
dirtyWidgets += delta;
var isDirty = dirtyWidgets > 0;
if ( wasDirty != isDirty)
markDirty(dirtyWidgets > 0);
}
void addDirty(int delta) {
var wasDirty = dirtyWidgets > 0;
dirtyWidgets += delta;
var isDirty = dirtyWidgets > 0;
if ( wasDirty != isDirty)
markDirty(dirtyWidgets > 0);
}