Storage Monitor Linux: Do not try to initialize MediaTransferProtocolManager during unit tests.

chrome/browser/storage_monitor/storage_monitor_linux_unittest.cc

Index: chrome/browser/storage_monitor/storage_monitor_linux_unittest.cc
===================================================================
--- chrome/browser/storage_monitor/storage_monitor_linux_unittest.cc	(revision 190492)
+++ chrome/browser/storage_monitor/storage_monitor_linux_unittest.cc	(working copy)
@@ -164,6 +164,10 @@
     message_loop_->PostTask(FROM_HERE, MessageLoop::QuitClosure());
   }
 
+  virtual bool IsRunningTest() const OVERRIDE {
+    return true;
+  }
+
   MessageLoop* message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(TestStorageMonitorLinux);