build: Treat warnings as errors (#923)

* squash and rebase andronov-alexey:treat_warnings_as_errors from pull request #850
* fix remaining warnings in java lib

src/lib_cxx/data/parser/cxx/utilityClang.cpp

@@ -68,6 +68,8 @@ AccessKind utility::convertAccessSpecifier(clang::AccessSpecifier access)
 		return ACCESS_PRIVATE;
 	case clang::AS_none:
 		return ACCESS_NONE;
+	default:
+		return ACCESS_NONE;
 	}
 }
 
@@ -85,6 +87,8 @@ SymbolKind utility::convertTagKind(const clang::TagTypeKind tagKind)
 		return SYMBOL_ENUM;
 	case clang::TTK_Interface:
 		return SYMBOL_KIND_MAX;
+	default:
+		return SYMBOL_KIND_MAX;
 	}
 }