fixes tinderbox orange (see bug 132517 for more info) sr=bryner

git-svn-id: svn://10.0.0.236/trunk@150392 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/modules/libpref/src/nsSafeSaveFile.cpp

@@ -77,6 +77,19 @@ nsresult nsSafeSaveFile::OnSaveFinished(PRBool aSaveSucceeded, PRBool aBackupTar
   if (aSaveSucceeded) {
     NS_ENSURE_STATE(mTargetFile && mTempFile);
 
+    if (!mTargetFileExists) {
+      // If the target file did not exist when we were initialized, then the
+      // temp file we gave out was actually a reference to the target file.
+      // since we succeeded in writing to the temp file (and hence succeeded
+      // in writing to the target file), there is nothing more to do.
+#ifdef DEBUG      
+      PRBool equal;
+      if (NS_FAILED(mTargetFile->Equals(mTempFile, &equal)) || !equal)
+        NS_ERROR("mTempFile not equal to mTargetFile");
+#endif
+      return NS_OK;      
+    }
+
     nsCAutoString targetFilename;
     rv = mTargetFile->GetNativeLeafName(targetFilename);