Add C# codegen changes to enum value names (mostly C++)

Overview of changes:
- A new C#-specific command-line option, legacy_enum_values to revert to the old behavior
- When legacy_enum_values isn't specified, we strip the enum name as a prefix, and PascalCase the value name
- A new attribute within the C# code so that we can always tell the original in-proto name

Regenerating the C# code with legacy_enum_values leads to code which still compiles and works - but
there's more still to do.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/google/protobuf/compiler/csharp/csharp_helpers.h b/src/google/protobuf/compiler/csharp/csharp_helpers.h
index eaf85014..8830e957 100644
--- a/src/google/protobuf/compiler/csharp/csharp_helpers.h
+++ b/src/google/protobuf/compiler/csharp/csharp_helpers.h
@@ -93,6 +93,8 @@ inline std::string UnderscoresToCamelCase(const std::string& input, bool cap_nex
 
 std::string UnderscoresToPascalCase(const std::string& input);
 
+std::string GetEnumValueName(const std::string& enum_name, const std::string& enum_value_name);
+
 // TODO(jtattermusch): perhaps we could move this to strutil
 std::string StringToBase64(const std::string& input);