New method Array::resize(). Tweaked AudioThumbnail to avoid clearing the input source when loaded. New class SingleThreadedReferenceCountedObject (and used this for Font, Typeface, Expression, Value and ValueTree classes, since none of these were safe to use with threads anyway). Minor additions to GlyphArrangement.

src/gui/graphics/contexts/juce_LowLevelGraphicsSoftwareRenderer.cpp

@@ -1018,7 +1018,7 @@ private:
 };
 
 //==============================================================================
-class ClipRegionBase  : public ReferenceCountedObject
+class ClipRegionBase  : public SingleThreadedReferenceCountedObject
 {
 public:
     ClipRegionBase() {}