Improve space substitution error correction.

Bug: 17432052

[Category diff]
+1     262
-1      93
+2       2
-2      18
+3      18
-3       2
+4     111
-4     148
+5     295
-5     217
+6      51
-6     276
+7     139
-7     124

[Weighted category diff]
+1     276
-1     100
+2       4
-2      20
+3      20
-3       4
+4     118
-4     160
+5     309
-5     225
+6      52
-6     298
+7     163
-7     135

show diff for ./en_user_log_phones_2011_08.csv
+1     173
-1      28
+2       2
-2      17
+3      17
-3       2
+4      63
-4      82
+5     120
-5      51
+6      24
-6     220
+7      88
-7      87

Change-Id: I9d673acb0ff632828ae2e0ead56e76e3a20411c6