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BUG=skia:

Review URL: https://codereview.chromium.org/1405083008

src/ports/SkDebug_win.cpp

@@ -23,7 +23,7 @@ void SkDebugf(const char format[], ...) {
     va_start(args, format);
     vfprintf(stderr, format, args);
     va_end(args);
-    fflush(stderr);
+    fflush(stderr);  // stderr seems to be buffered on Windows.
 
     va_start(args, format);
     vsnprintf(buffer, kBufferSize, format, args);