Improved CPU efficiency of MessageManager::runDispatchLoopUntil() on OSX

modules/juce_events/native/juce_mac_MessageManager.mm

@@ -389,18 +389,19 @@ bool MessageManager::runDispatchLoopUntil (int millisecondsToRunFor)
     {
         JUCE_AUTORELEASEPOOL
         {
-            CFRunLoopRunInMode (kCFRunLoopDefaultMode, 0.001, true);
+            auto msRemaining = endTime - Time::currentTimeMillis();
 
-            NSEvent* e = [NSApp nextEventMatchingMask: NSEventMaskAny
-                                            untilDate: [NSDate dateWithTimeIntervalSinceNow: 0.001]
-                                               inMode: NSDefaultRunLoopMode
-                                              dequeue: YES];
+            if (msRemaining <= 0)
+                break;
 
-            if (e != nil && (isEventBlockedByModalComps == nullptr || ! (*isEventBlockedByModalComps) (e)))
-                [NSApp sendEvent: e];
+            CFRunLoopRunInMode (kCFRunLoopDefaultMode, jmin (1.0, msRemaining * 0.001), true);
 
-            if (Time::currentTimeMillis() >= endTime)
-                break;
+            if (NSEvent* e = [NSApp nextEventMatchingMask: NSEventMaskAny
+                                                untilDate: [NSDate dateWithTimeIntervalSinceNow: 0.001]
+                                                   inMode: NSDefaultRunLoopMode
+                                                  dequeue: YES])
+                if (isEventBlockedByModalComps == nullptr || ! (*isEventBlockedByModalComps) (e))
+                    [NSApp sendEvent: e];
         }
     }