Support Unicode build on Windows

appveyor.bat

@@ -10,7 +10,7 @@ goto :error
 echo Building C++
 mkdir build_msvc
 cd build_msvc
-cmake -G "%generator%" -Dprotobuf_BUILD_SHARED_LIBS=%BUILD_DLL% ../cmake
+cmake -G "%generator%" -Dprotobuf_BUILD_SHARED_LIBS=%BUILD_DLL% -DUNICODE=%UNICODE% ../cmake
 msbuild protobuf.sln /p:Platform=%vcplatform% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" || goto error
 cd %configuration%
 tests.exe || goto error

appveyor.yml

@@ -11,6 +11,7 @@ environment:
   matrix:
     - language: cpp
       BUILD_DLL: ON
+      UNICODE: ON
 
     - language: csharp
 

cmake/CMakeLists.txt

@@ -159,6 +159,10 @@ else (MSVC)
   set(LIB_PREFIX)
 endif (MSVC)
 
+if (UNICODE)
+  add_definitions(-DUNICODE -D_UNICODE)
+endif (UNICODE)
+
 include(libprotobuf-lite.cmake)
 include(libprotobuf.cmake)
 include(libprotoc.cmake)

src/google/protobuf/testing/file.cc

@@ -141,12 +141,12 @@ void File::DeleteRecursively(const string& name,
 
 #ifdef _MSC_VER
   // This interface is so weird.
-  WIN32_FIND_DATA find_data;
-  HANDLE find_handle = FindFirstFile((name + "/*").c_str(), &find_data);
+  WIN32_FIND_DATAA find_data;
+  HANDLE find_handle = FindFirstFileA((name + "/*").c_str(), &find_data);
   if (find_handle == INVALID_HANDLE_VALUE) {
     // Just delete it, whatever it is.
-    DeleteFile(name.c_str());
-    RemoveDirectory(name.c_str());
+    DeleteFileA(name.c_str());
+    RemoveDirectoryA(name.c_str());
     return;
   }
 
@@ -156,15 +156,15 @@ void File::DeleteRecursively(const string& name,
       string path = name + "/" + entry_name;
       if (find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
         DeleteRecursively(path, NULL, NULL);
-        RemoveDirectory(path.c_str());
+        RemoveDirectoryA(path.c_str());
       } else {
-        DeleteFile(path.c_str());
+        DeleteFileA(path.c_str());
       }
     }
-  } while(FindNextFile(find_handle, &find_data));
+  } while(FindNextFileA(find_handle, &find_data));
   FindClose(find_handle);
 
-  RemoveDirectory(name.c_str());
+  RemoveDirectoryA(name.c_str());
 #else
   // Use opendir()!  Yay!
   // lstat = Don't follow symbolic links.