[jdk25u] RFR: 8359428: Test 'javax/swing/JTabbedPane/bug4499556.java' failed because after selecting one of L&F items, the test case automatically failed when clicking on L&F Menu button again

[Srinivas Mandalika]

**PR Changes**
It is seen that this test (which was opensourced in [JDK-8353304](https://bugs.openjdk.org/browse/JDK-8353304)) when run with NimbusLookAndFeel, after selecting one of L&F items, the test case automatically failed when clicking on L&F Menu button again.
It is because while switching to another L&F say platform(WindowsL&F) from Metal/Nimbus LookAndFeel, if testcase was originally run in Nimbus L&F, SynthMenuItemLayoutHelper() calls MenuItemLayoutHelper.reset where style.getFont(context) return null font so when it calls getFontMetrics(font) it calls font.hashCode which fails with

Execution failed: `main' threw exception: java.lang.NullPointerException: Cannot invoke "java.awt.Font.hashCode()" because "font" is null

This is happening because the test calls SwingUtilities.updateComponentTreeUI on tabbedpane.
So, when L&F is changed inside the test via "L&F Menu" option 1st time say Metal to Platform, it changes the L&F of the tabbed pane to Windows L&F, but not for the "L&F Menu" font itself which is still in Nimbus L&F, but style context is reset so when next time "L&F Menu" is clicked to change the L&F, SynthMenuItemLayoutHelper gets null font from invalid context and then it crashes.
Fix is to ensure the updateComponentTreeUI should be for entire frame which consists of "L&F Menu" and the tabs so L&F is changed consistently for all nodes.

**Testing**

 [JTREG Testing] (1 manual test )

runner starting test: javax/swing/JTabbedPane/bug4499556.java

runner finished test: javax/swing/JTabbedPane/bug4499556.java

Passed. Execution successful

Test results: passed: 1

**Conflicts**
[MR clean check] (A Clean Backport) -Yes

[Are higher backports completed(25u,21u,17u,11u,8u etc) ?]
Applicable to 25u via this MR and the others are being worked upon.

 [Does it contain multiple changesets ?] - No

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Commit messages:
 - Backport 2b94b70ef50675f7853c0cb6a61e60e6eb7d92ed

Changes: https://git.openjdk.org/jdk25u/pull/50/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u&pr=50&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8359428
  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk25u/pull/50.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u.git pull/50/head:pull/50

PR: https://git.openjdk.org/jdk25u/pull/50