RFR: 8297241: Update sun/java2d/DirectX/OnScreenRenderingResizeTest/OnScreenRenderingResizeTest.java

[Jayathirth D V]

This is follow up of https://github.com/openjdk/jdk/pull/11158#discussion_r1025574199

I have added empty paint() and update() methods back for the frame in this test.
Ran the test 20 times in our CI machines on all platforms. It failed once in Linux machine and image dump showed nothing was drawn.

Added robot.waitForIdle() after frame.resize() also so that system-triggered repaint can be finished after resize of the frame. With this update i don't see this test failing on all platforms in our CI even when run for 100 times.

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Commit messages:
 - Add empty paint method and waitForIdle for resize

Changes: https://git.openjdk.org/jdk/pull/11237/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11237&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297241
  Stats: 7 lines in 1 file changed: 6 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/11237.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11237/head:pull/11237

PR: https://git.openjdk.org/jdk/pull/11237