Fixing the issues 392440 and 434912

The [issue 392440](https://bugs.eclipse.org/bugs/show_bug.cgi?id=392440) concerns the lake of the ```this``` keyword before the object's fields in the ```JvmTypesBuilder.toHashCodeMethod()```.

The [issue 434912](https://bugs.eclipse.org/bugs/show_bug.cgi?id=434912) concerns the lake of the ```this``` keyword before the object's fields in the ```JvmTypesBuilder.toEqualsMethod()```.