Annotate static fields with accessibility

This mirrors the annotation already present on methods, and is needed to
resolve indirect reference to an inherited static field, similar to virtual
call resolution. The access attribute is set as a comment so that in an assignment
some_static_field = some_constant we don't need to attach spurious access tags
to the constant, or scrub them from the field, for their types to be considered
matching.

Author: smowton

src/java_bytecode/java_bytecode_convert_class.cpp

@@ -391,6 +391,20 @@ void java_bytecode_convert_classt::convert(
       "."+id2string(f.name);
     new_symbol.mode=ID_java;
     new_symbol.is_type=false;
+
+    // These annotations use `ID_C_access` instead of `ID_access` like methods
+    // to avoid type clashes in expressions like `some_static_field = 0`, where
+    // with ID_access the constant '0' would need to have an access modifier
+    // too, or else appear to have incompatible type.
+    if(f.is_public)
+      new_symbol.type.set(ID_C_access, ID_public);
+    else if(f.is_protected)
+      new_symbol.type.set(ID_C_access, ID_protected);
+    else if(f.is_private)
+      new_symbol.type.set(ID_C_access, ID_private);
+    else
+      new_symbol.type.set(ID_C_access, ID_default);
+
     const namespacet ns(symbol_table);
     new_symbol.value=
       zero_initializer(