[8] Review request for 8011059 [macosx] Make JDK demos look perfect on retina displays

[Alexander Scherbatiy]

Hello,

Could you review the fix:

   bug: https://bugs.openjdk.java.net/browse/JDK-8011059
   webrev: http://cr.openjdk.java.net/~alexsch/8011059/webrev.00

   The IMAGE_SCALING rendering hint is added to the RenderingHints class.
   Enabling the image scaling rendering hint forces the SunGraphics2D to 
use getScaledInstance(width, height, hints) method
   from Image class with SCALE_DEFAULT hint.

   By default the image scaling rendering hint is enabled on HiDPI 
display and disabled for standard displays.

   User can override the getScaledInstance(width, height, hints) method 
and return necessary high resolution image
   according to the given image width and height.

   For example:
   ---------------------
         final Image highResolutionImage =
                 new BufferedImage(2 * WIDTH, 2 * HEIGHT, 
BufferedImage.TYPE_INT_RGB);
         Image image = new BufferedImage(WIDTH, HEIGHT, 
BufferedImage.TYPE_INT_RGB) {

             @Override
             public Image getScaledInstance(int width, int height, int 
hints) {
                 if ((hints & Image.SCALE_DEFAULT) != 0) {
                     return (width <= WIDTH && height <= HEIGHT)
                             ? this : highResolutionImage;
                 }
                 return super.getScaledInstance(width, height, hints);
             }
         };
   ---------------------

   The LWCToolkit and ToolkitImage classes are patched to automatically 
get provided image at 2x.ext images on MacOSX.

   There are no significant changes in the Java2D demo to make it look 
perfect on Retina displays.
   It needs only to put necessary images with the @2x postfix  and they 
will be automatically drawn.

Thanks,
Alexandr.