Bug 1268723: Make it clear that the TestCrashyOperation crashes are expected. r=njn

--HG--
extra : rebase_source : e2e8e6272aa8e80cd4b3db6828009555d4f5311e

xpcom/tests/gtest/TestPLDHash.cpp

@@ -56,6 +56,7 @@ TestCrashyOperation(void (*aCrashyOperation)())
 #endif
 
     // Child: perform the crashy operation.
+    fprintf(stderr, "TestCrashyOperation: The following crash is expected. Do not panic.\n");
     aCrashyOperation();
     fprintf(stderr, "TestCrashyOperation: didn't crash?!\n");
     ASSERT_TRUE(false);   // shouldn't reach here