Manual test for leakage.
review fixes.
Merge pull request #436 from baxissimo/instancing-leakage-test

Add a manual conformance test for ANGLE_instanced_arrays state leakage.
fix bug link. crbug.com, not crbug.org.
Merge pull request #438 from baxissimo/fix-link-in-test

Fix bug link. Should be "crbug.com", not "crbug.org".