Add more entries to the confusability mapping

U+014B (ŋ) => n
U+1004 (င) => c
U+100c (ဌ) => g
U+1042 (၂) => j
U+1054 (ၔ) => e

Bug: 811117,808316
Test: components_unittests -gtest_filter=*IDN*
Change-Id: I29f73c48d665bd9070050bd7f0080563635b9c63
Reviewed-on: https://chromium-review.googlesource.com/919423
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Jungshik Shin <jshin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536955}