Move unit tests to test/unittests.

test/unittests/base/platform/condition-variable-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/platform/condition-variable.h"
 
 #include "src/base/platform/platform.h"
 #include "src/base/platform/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 281 matching lines @@
       delete threads[n];
     }
     delete[] threads;
 
     EXPECT_EQ(limit, counter);
   }
 }
 
 }  // namespace base
 }  // namespace v8