"cannot resolve symbol" is a terrible diagnostic

The "cannot resolve symbol" diagnostic is one of the two most common
error messages printed by javac (the other being a syntax error).
This diagnostic is terrible. First, the problem is not in name resolution.
Name resolution is a dynamic thing that happens at runtime. Rather, it is
a problem of name lookup, which is a static thing that happens at compile
time. A much better diagnostic would be something like "name undefined".