Replace all usages of method references (aka ::) with lambdas

[markushi]

Description

As discussed here using method references might causes issues in combination with older version of the AGP.

Overall there are quite some usages of method references(>50), but since this issue is only relevant on Android, it only needs to be fixed for those parts.

E.g. JsonObjectSerializer.java

case STRING:
        done = handlePrimitive(reader::nextString);

should be replaced by

case STRING:
        done = handlePrimitive(() -> reader.nextString());