RFR: 8303082 : [AIX] Missing C++ name demangling with XLClang++ [v4]

[Deepa Kumari]

> It was failing as It was using the C++ demangling interface (Demangle) of the old demangler (that is, the C++ API as opposed to the C one). It is not supported by xlclang++ on AIX.
> To demangle names generated by xlclang++ , use cxxabi.h __cxa_demangle interface ( see cxxabi.h).
> 
> This Solution applies to the following test 
> 
> 1. SecondaryErrorTest.java`
> 2. TestSigInfoInHsErrFile.java
> 
> 
> Reported Issue : [JDK - 8303082](https://bugs.openjdk.org/browse/JDK-8303082)

Deepa Kumari has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:

  8303082 : [AIX] Missing C++ name demangling with XLClang++

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12742/files
  - new: https://git.openjdk.org/jdk/pull/12742/files/49f0267e..1b05a7df

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12742&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12742&range=02-03

  Stats: 3 lines in 1 file changed: 2 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/12742.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/12742/head:pull/12742

PR: https://git.openjdk.org/jdk/pull/12742