dispose method
Releases the resources associated with this painter.
After disposal this painter is unusable.
Implementation
void dispose() {
assert(!debugDisposed);
assert(() {
_disposed = true;
return true;
}());
assert(debugMaybeDispatchDisposed(this));
_layoutTemplate?.dispose();
_layoutTemplate = null;
_layoutCache?.paragraph.dispose();
_layoutCache = null;
_text = null;
}