Fix windows build.

TBR=mnaganov@chromium.org

Review URL: http://codereview.chromium.org/6901125

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7730 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/log.cc

@@ -469,7 +469,7 @@ class Logger::NameBuffer {
     for (int i = 0; i < uc16_length && utf8_pos_ < kUtf8BufferSize; ++i) {
       uc16 c = uc16_buffer_[i];
       if (c <= String::kMaxAsciiCharCodeU) {
-        utf8_buffer_[utf8_pos_++] = c;
+        utf8_buffer_[utf8_pos_++] = static_cast<char>(c);
       } else {
         int char_length = unibrow::Utf8::Length(c);
         if (utf8_pos_ + char_length > kUtf8BufferSize) break;