RFR: 8221478: Disable VerifySharedSpaces by default

[Claes Redestad]

Hi David,

On 2019-05-03 04:49, David Holmes wrote:
> Hi Claes,
> 
> This looks fine to me.

thanks!

I ran into a test which depends on content verification to detect errors
due to deliberate corruption of the archive. I updated the test to turn
on VerifySharedSpaces explicitly for the subset of cases where content
corruption is the expected cause for failure (without verification these
tests might crash rather than fail, which is an expected outcome of this
behavior change):

http://cr.openjdk.java.net/~redestad/8221478/open.01/

Otherwise tier1-4 is green.

/Claes