Structural equivalence does not check for isExplicitlyDefaulted.

[balazske]

In isStructurallyEquivalent (CXXMethodDecl) there is no check for the isExplicitlyDefaulted property. This can be different from isDefaulted (I think isDefaulted is true when the function is default but generated by the compiler, and isExplicitlyDefaulted means there was a =default in the code.)