RFR: 8225777: java/awt/Mixing/MixingOnDialog.java fails on Ubuntu [v4]

[Alexander Zvegintsev]

> The test was failing due to it tried to place windows too close to left top corner, so they got shifted from the dock and top panel on Gnome.
> 
> Shifting all test windows fixes the issue.
> 
> 
> Testing is green on all platforms.

Alexander Zvegintsev has updated the pull request incrementally with one additional commit since the last revision:

  review comments

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8326/files
  - new: https://git.openjdk.java.net/jdk/pull/8326/files/a6f180aa..7b5e49ea

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8326&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8326&range=02-03

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8326.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8326/head:pull/8326

PR: https://git.openjdk.java.net/jdk/pull/8326