Return specific cert verification errors on Android

To implement CertVerifyProc on Android we refer to the Java 
side to query the platform trust managers. Currently the 
information we get from the platform is binary - each 
certificate chain is either identified as trusted or not, in 
which case we assume that this is due to not-trusted root.

This patch provides better granularity distinguishing the 
following cases: expired, not yet valid, incorrect (could not 
be parsed), not trusted root.

This allowed to reenable two net unittests:
- CertVerifyProcTest.ExtraneousMD5RootCert
- CertVerifyProcTest.IntermediateCARequireExplicitPolicy

The following net unittest had to be disabled as it joins 
the club of CertVerifyProc tests failing on bots with 
incorrect time/date settings:
- CertVerifyProcTest.InvalidKeyUsage

BUG=169762

Review URL: https://chromiumcodereview.appspot.com/12212135

git-svn-id: http://src.chromium.org/svn/trunk/src/build@182280 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

android/pylib/gtest/filter/net_unittests_disabled

@@ -1,6 +1,4 @@
 # List of suppressions.
-CertVerifyProcTest.ExtraneousMD5RootCert
-CertVerifyProcTest.IntermediateCARequireExplicitPolicy
 CertVerifyProcTest.PublicKeyHashes
 CertVerifyProcTest.RejectWeakKeys
 CertVerifyProcTest.VerifyReturnChainBasic
@@ -40,6 +38,7 @@ VerifyRoot/CertVerifyProcWeakDigestTest.Verify/2
 # Fail only on bots.
 CertVerifyProcTest.TestKnownRoot
 CertVerifyProcTest.WithoutRevocationChecking
+CertVerifyProcTest.InvalidKeyUsage
 HttpCache.RangeGET_Cancel
 HttpCache.RangeGET_Cancel2
 HttpCache.RangeGET_OK