message: Ensure that tflite::task::core::ErrorReporter::message() returns an empty string,
  rather than uninitialized bytes, if there hasn't been any previous message.
diff: @@ -16,6 +16,7 @@ limitations under the License.
  #ifndef TENSORFLOW_LITE_SUPPORT_CC_TASK_CORE_ERROR_REPORTER_H_
  #define TENSORFLOW_LITE_SUPPORT_CC_TASK_CORE_ERROR_REPORTER_H_
  +#include <cstdarg>
  #include <string>
  #include "tensorflow/lite/stateful_error_reporter.h"
  @@ -27,12 +28,14 @@ namespace core {
  // An ErrorReporter that logs to stderr and captures the last message.
  class ErrorReporter : public tflite::StatefulErrorReporter {
  public:
  + ErrorReporter() { last_message_[0] = '\0'; }
  +
  // We declared two functions with name 'Report', so that the variadic Report
  // function in tflite::ErrorReporter is hidden.
  // See https://isocpp.org/wiki/faq/strange-inheritance#hiding-rule.
  using tflite::ErrorReporter::Report;
  - int Report(const char* format, va_list args) override;
  + int Report(const char* format, std::va_list args) override;
  std::string message() override;
  