Reviewed-by: tschatzl, jwilhelm

8060467: CMS: small OldPLABSize and -XX:-ResizePLAB cause assert(ResizePLAB || n_blks == OldPLABSize) failed: Error
Reviewed-by: tschatzl, jmasa, kbarrett

8014489: tests/gc/arguments/Test(Serial|CMS|Parallel|G1)HeapSizeFlags jtreg tests invoke wrong class
Summary: Some jtreg tests reference unknown classes in the @run and @build lines. This change fixes them.
Reviewed-by: stefank, ehelin

Summary: The patch for 8006088 misses regression tests after a merge error, this CR provides them.
Reviewed-by: jwilhelm, tamao, jmasa

Reviewed-by: ehelin, jwilhelm, jmasa