Made a couple of MidiFile methods const

modules/juce_audio_basics/midi/juce_MidiFile.cpp

@@ -363,7 +363,7 @@ void MidiFile::convertTimestampTicksToSeconds()
 }
 
 //==============================================================================
-bool MidiFile::writeTo (OutputStream& out, int midiFileType)
+bool MidiFile::writeTo (OutputStream& out, int midiFileType) const
 {
     jassert (midiFileType >= 0 && midiFileType <= 2);
 
@@ -381,7 +381,7 @@ bool MidiFile::writeTo (OutputStream& out, int midiFileType)
     return true;
 }
 
-bool MidiFile::writeTrack (OutputStream& mainOut, const MidiMessageSequence& ms)
+bool MidiFile::writeTrack (OutputStream& mainOut, const MidiMessageSequence& ms) const
 {
     MemoryOutputStream out;
 

modules/juce_audio_basics/midi/juce_MidiFile.h

@@ -174,7 +174,7 @@ public:
 
         @returns true if the operation succeeded.
     */
-    bool writeTo (OutputStream& destStream, int midiFileType = 1);
+    bool writeTo (OutputStream& destStream, int midiFileType = 1) const;
 
     /** Converts the timestamp of all the midi events from midi ticks to seconds.
 
@@ -183,14 +183,13 @@ public:
     */
     void convertTimestampTicksToSeconds();
 
-
 private:
     //==============================================================================
     OwnedArray<MidiMessageSequence> tracks;
     short timeFormat;
 
     void readNextTrack (const uint8*, int, bool);
-    bool writeTrack (OutputStream&, const MidiMessageSequence&);
+    bool writeTrack (OutputStream&, const MidiMessageSequence&) const;
 
     JUCE_LEAK_DETECTOR (MidiFile)
 };