Enhancement: Add a Japanese input test

[naokomc]

To identify bugs around Japanese input method and multibyte character display, add a test to see if a certain input results in desired output.

Based on The Big List of Naughty Strings, I think adding an input test for this one modified string is a good starting point.

田中がパーティへ行く (^_-)

There are two types of Japanese input methods on iOS, and each needs to be tested with both HTML and standard (visual) modes. So the complete variations are:

• Kana (QWERTY) Keyboard + HTML
• Kana Keyboard + visual
• Flick Keyboard + HTML
• Flick Keyboard + visual

For Kana/QWERTY, it's a matter of typing "tanakagapa-texiheiku (^_-)" and selecting the correct suggested kanji + kana combinations. For Flick, I may have to record a video or something because it's difficult to explain in writing.

Using Japanese Kana/Flick Keyboard

1. Add Japanese kana/flick Keyboard (Settings -> General -> Keyboards -> Add New Keyboard, then select Japanese -> Kana)
2. Open WP for iOS app, and start a new post.
3. While in the text field, tap the globe icon in the keypad to switch between keyboards.

[sendhil]

cc @bummytime