Don't buffer stdout in DM

dm/DM.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "CrashHandler.h"
 #include "DMJsonWriter.h"
 #include "DMSrcSink.h"
@@ skipping 1253 matching lines @@
     }
     return nullptr;
 }
 
 #undef PORTABLE_FONT_PREFIX
 
 extern SkTypeface* (*gCreateTypefaceDelegate)(const char [], SkTypeface::Style );
 
 int dm_main();
 int dm_main() {
+    setbuf(stdout, nullptr);
     setup_crash_handler();
 
     if (FLAGS_verbose) {
         gVLog = stderr;
     } else if (!FLAGS_writePath.isEmpty()) {
         sk_mkdir(FLAGS_writePath[0]);
         gVLog = freopen(SkOSPath::Join(FLAGS_writePath[0], "verbose.log").c_str(), "w", stderr);
     }
 
     JsonWriter::DumpJson();  // It's handy for the bots to assume this is ~never missing.
@@ skipping 134 matching lines @@
 #endif
 }
 } // namespace skiatest
 
 #if !defined(SK_BUILD_FOR_IOS)
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return dm_main();
 }
 #endif