Remove GlVboPerfTest tests from known failures.

testVboVsNonVboPerfGeometry0 and
testVboVsNonVboPerfGeometry1 pass as expected.

Move testVboWithVaryingIndexBufferNumbers to a separate bug
because it is a different failure.

bug:17394321
Change-Id: Ie64c38bbbd279fc5c2fa74e515789db34adeaed9
diff --git a/tests/expectations/knownfailures.txt b/tests/expectations/knownfailures.txt
index ae78695..de3a60a 100644
--- a/tests/expectations/knownfailures.txt
+++ b/tests/expectations/knownfailures.txt
@@ -86,14 +86,18 @@
   description: "permissions for the API previously used in the test has changed, making it impossible to pass",
   names: [
     "android.openglperf.cts.GlAppSwitchTest#testGlActivitySwitchingFast",
-    "android.openglperf.cts.GlAppSwitchTest#testGlActivitySwitchingSlow",
-    "android.openglperf.cts.GlVboPerfTest#testVboVsNonVboPerfGeometry0",
-    "android.openglperf.cts.GlVboPerfTest#testVboVsNonVboPerfGeometry1",
-    "android.openglperf.cts.GlVboPerfTest#testVboWithVaryingIndexBufferNumbers"
+    "android.openglperf.cts.GlAppSwitchTest#testGlActivitySwitchingSlow"
   ],
   bug: 17394321
 },
 {
+  description: "unexpected failures",
+  names: [
+    "android.openglperf.cts.GlVboPerfTest#testVboWithVaryingIndexBufferNumbers"
+  ],
+  bug: 18091590
+},
+{
   description: "these tests require a good test scene, so they fail if run in random conditions",
   names: [
     "android.hardware.camera2.cts.AllocationTest#testBlackWhite",