backport: Use the actual system-packages from the JVM for export

[gireeshpunathil]

Fixes eclipse-pde/eclipse.pde#194 for PDE-build in 4.23

Refs: eclipse-pde/eclipse.pde#624

/cc @HannesWell

[gireeshpunathil]

surprisingly, ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/TargetPlatformHelper.java is appearing a completely new file in this web interface! is this some sort of a bug? or am I making anything wrong?

[HannesWell]

surprisingly, ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/TargetPlatformHelper.java is appearing a completely new file in this web interface! is this some sort of a bug? or am I making anything wrong?

o.e.pde.core always lived in PDE's 'main' repo and was never in this one.
If the backported commit contains changes in that file it has to be done in the other repo on the corresponding maintance branch, if it is not already there.

Probably the best is to have both repos checked out at the R4_23 branch and import the pde.build projects from this repo and then make it work.

[gireeshpunathil]

fyi - this is the only change that was required for the back port on top of @HannesWell 's original PR

from org.eclipse.jdt.launching;bundle-version="[3.19.700,4.0.0)"
to org.eclipse.jdt.launching;bundle-version="[3.2.0,4.0.0)"

to match what is in there for 4.23

[gireeshpunathil]

for that reason I intent to keep the second commit as is rather than squashing, but let me know if you think otherwise. (I understand that each project may have different rules)

[HannesWell]

That's reasonable, would keep it separated too.

[vik-chand]

" > surprisingly, ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/TargetPlatformHelper.java is appearing a

Probably the best is to have both repos checked out at the R4_23 branch and import the pde.build projects from this repo and then make it work. :"

Yes, also knowing that the change is in 1-2 files ( max 3 files) should make this easier

[HannesWell]

LGTM
But I havn't checked the code, assuming you left it unchanged.

[gireeshpunathil]

But I havn't checked the code, assuming you left it unchanged.

yes, no change in the code except downgrading of org.eclipse.jdt.launching to match the 4.23 prevalence.