avoid_dynamic_calls

Method invocation or property access on a 'dynamic' target.

The analyzer produces this diagnostic when a member of a class is accessed on an expression whose type is dynamic.

The following code produces this diagnostic because the getter length is being invoked on s, which has the type dynamic:

void f(dynamic s) {
  s.length;
}

Provide enough type information that the expression has a type other than dynamic:

void f(String s) {
  s.length;
}