Allow MSVC to build non-lite mode

c++/CMakeLists.txt

@@ -34,11 +34,6 @@ if(CAPNP_LITE AND BUILD_TESTING AND NOT EXTERNAL_CAPNP)
   message(SEND_ERROR "You must set EXTERNAL_CAPNP when using CAPNP_LITE and BUILD_TESTING.")
 endif()
 
-
-if(MSVC AND NOT CAPNP_LITE)
-  message(SEND_ERROR "Building with MSVC is only supported with CAPNP_LITE.")
-endif()
-
 if(CAPNP_LITE)
   set(CAPNP_LITE_FLAG "-DCAPNP_LITE")
   # This flag is attached as PUBLIC target_compile_definition to kj target

c++/src/capnp/common.h

@@ -44,11 +44,6 @@ namespace capnp {
 #define CAPNP_VERSION \
   (CAPNP_VERSION_MAJOR * 1000000 + CAPNP_VERSION_MINOR * 1000 + CAPNP_VERSION_MICRO)
 
-#ifdef _MSC_VER
-#define CAPNP_LITE 1
-// MSVC only supports "lite" mode for now, due to missing C++11 features.
-#endif
-
 #ifndef CAPNP_LITE
 #define CAPNP_LITE 0
 #endif

c++/src/kj/common.h

@@ -63,9 +63,6 @@
 #elif defined(_MSC_VER)
   #if _MSC_VER < 1900
     #error "You need Visual Studio 2015 or better to compile this code."
-  #elif !CAPNP_LITE
-    // TODO(cleanup): This is KJ, but we're talking about Cap'n Proto.
-    #error "As of this writing, Cap'n Proto only supports Visual C++ in 'lite mode'; please #define CAPNP_LITE"
   #endif
 #else
   #warning "I don't recognize your compiler.  As of this writing, Clang and GCC are the only "\