Stop warnings resulting from unimplemented SetProcessBackgrounded().

base/process/process_unittest.cc

 // Copyright 2014 The Chromium 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 "base/process/process.h"
 
 #include "base/process/kill.h"
 #include "base/test/multiprocess_test.h"
 #include "base/test/test_timeouts.h"
 #include "base/threading/platform_thread.h"
@@ skipping 158 matching lines @@
 // a process. The calls to SetProcessBackground should be noops then.
 TEST_F(ProcessTest, SetProcessBackgrounded) {
   Process process(SpawnChild("SimpleChildProcess"));
   int old_priority = process.GetPriority();
 #if defined(OS_WIN)
   EXPECT_TRUE(process.SetProcessBackgrounded(true));
   EXPECT_TRUE(process.IsProcessBackgrounded());
   EXPECT_TRUE(process.SetProcessBackgrounded(false));
   EXPECT_FALSE(process.IsProcessBackgrounded());
 #else
-  process.SetProcessBackgrounded(true);
-  process.SetProcessBackgrounded(false);
+  if (process.CanBackgroundProcesses()) {
+    process.SetProcessBackgrounded(true);
+    process.SetProcessBackgrounded(false);
+  }
 #endif
   int new_priority = process.GetPriority();
   EXPECT_EQ(old_priority, new_priority);
 }
 
 // Same as SetProcessBackgrounded but to this very process. It uses
 // a different code path at least for Windows.
 TEST_F(ProcessTest, SetProcessBackgroundedSelf) {
   Process process = Process::Current();
   int old_priority = process.GetPriority();
 #if defined(OS_WIN)
   EXPECT_TRUE(process.SetProcessBackgrounded(true));
   EXPECT_TRUE(process.IsProcessBackgrounded());
   EXPECT_TRUE(process.SetProcessBackgrounded(false));
   EXPECT_FALSE(process.IsProcessBackgrounded());
 #else
   process.SetProcessBackgrounded(true);
   process.SetProcessBackgrounded(false);
 #endif
   int new_priority = process.GetPriority();
   EXPECT_EQ(old_priority, new_priority);
 }
 
 }  // namespace base