Fix gcc 4.7 build problem for cromo unittest.

Disabled unused variable warnings for unittest, because gTest
framework defines "testinfo" varibale for every test case, which is
not usually read.

TEST=unittest passed.
BUG=None

Change-Id: If6bd3fb7b2dc7fdfc5f0164312e89af9f403e825
Reviewed-on: https://gerrit.chromium.org/gerrit/31520
Reviewed-by: Eric Shienbrood <ers@chromium.org>
Tested-by: Han Shen <shenhan@chromium.org>
Commit-Ready: Han Shen <shenhan@chromium.org>
2 files changed