bug 113833 preventing initalization of trace malloc stuff unless

--trace-malloc command line is given. sr=dveditz

tools/trace-malloc/lib/nsTraceMalloc.c

@@ -1712,7 +1712,8 @@ PR_IMPLEMENT(int) NS_TraceMallocStartupArgs(int argc, char* argv[])
         }
     }
 
-    NS_TraceMallocStartup(logfd);
+    if (logfd >= 0)
+        NS_TraceMallocStartup(logfd);
     return argc;
 }
 

xpcom/base/nsTraceMalloc.c

@@ -1712,7 +1712,8 @@ PR_IMPLEMENT(int) NS_TraceMallocStartupArgs(int argc, char* argv[])
         }
     }
 
-    NS_TraceMallocStartup(logfd);
+    if (logfd >= 0)
+        NS_TraceMallocStartup(logfd);
     return argc;
 }