Fix the empty profile slow down the dex2oat

When pass in an empty profile to dex2oat, the dex2oat will still use the
empty prifle to do layout optimization, which is not necessary.

Bug: 204415663
Test: art_dex2oat_tests --gtest_filter=DexLayoutTest

Change-Id: Ice86d2c2c178ab96b5cd34bed204e6008fab34c8
1 file changed