NSViewComponentPeer: Fix occasional rendering artefacts

When clearing deferredRepaints in drawRect, dirty regions in the 'next'
frame could be incorrectly removed while drawing the 'current' frame.
Now, deferredRepaints is cleared in setNeedsDisplayRectangles, as it
was before 9d50ab6c59.

modules/juce_gui_basics/native/juce_NSViewComponentPeer_mac.mm

@@ -951,8 +951,6 @@ public:
         if (r.size.width < 1.0f || r.size.height < 1.0f)
             return;
 
-        deferredRepaints.subtract ({ convertToRectFloat (r) });
-
         auto cg = []
         {
             if (@available (macOS 10.10, *))
@@ -1114,6 +1112,11 @@ public:
             [view setNeedsDisplayInRect: makeNSRect (i)];
 
         lastRepaintTime = Time::getMillisecondCounter();
+
+       #if JUCE_COREGRAPHICS_RENDER_WITH_MULTIPLE_PAINT_CALLS
+        if (metalRenderer == nullptr)
+       #endif
+            deferredRepaints.clear();
     }
 
     void performAnyPendingRepaintsNow() override