Revert "Make ZipEntryTest time-insensitive"

Test fails:

    junit.framework.AssertionFailedError
    	at junit.framework.TestCase.assertTrue(TestCase.java:201)
    	at libcore.java.util.zip.ZipOutputStreamTest.testPutNextEntryUsingCurrentTime(ZipOutputStreamTest.java:126)
    	at java.lang.reflect.Method.invoke(Native Method)
    	at junit.framework.TestCase.runTest(TestCase.java:176)
    	at junit.framework.TestCase.runBare(TestCase.java:141)
    	at libcore.junit.junit3.TestCaseWithRules.superRunBare(TestCaseWithRules.java:110)
    	at libcore.junit.junit3.TestCaseWithRules.-wrap0(Unknown Source:0)
    	at libcore.junit.junit3.TestCaseWithRules$1.evaluate(TestCaseWithRules.java:66)
    	at dalvik.system.CloseGuardSupport$FailTestWhenResourcesNotClosedRule$1.evaluate(CloseGuardSupport.java:111)
    	at libcore.junit.junit3.TestCaseWithRules.runBare(TestCaseWithRules.java:106)
  libcore.java.util.zip.ZipOutputStreamTest#testPutNextEntryUsingCurrentTime FAIL (EXEC_FAILED)

Bug: 37696493

This reverts commit 27feef25.

Change-Id: I7b8d1b976e7f23465522e8b48f41183fcef49252