RFR: 8278828 : java/awt/a11y/AccessibleTextTest.java's createTextArea() just shows instructions on the UI

[lawrence.andrews]

1) Test scenario was just showing test instruction with JTextArea. So added the JTextArea as the instruction and method says. 
2) JTextArea is filled with contents so that and an Emoji character making sure that screen reader can read Emoji also.
3) Now user can user arrow keys to navigate the JTextArea and screen reader can read it.

@shurymury 

Attached the screen shot of the test UI which contains JTextArea along with the instruction.
<img width="623" alt="Screen Shot 2021-12-14 at 7 09 14 PM" src="https://user-images.githubusercontent.com/87324768/146111187-29f81aab-a138-442d-90bd-df24d512fe01.png">

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Commit messages:
 - Added JTextArea createTextArea() in AccessibleTextTest.java

Changes: https://git.openjdk.java.net/jdk/pull/6844/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6844&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8278828
  Stats: 9 lines in 1 file changed: 9 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6844.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6844/head:pull/6844

PR: https://git.openjdk.java.net/jdk/pull/6844