Suggestion-only user dictionary entry may not work

[yukawa]

Environment

• Android M 6.0.1 MTC20F (not specific to a certain Android OS version)
• Nexus 6P (not specific to a certain device)
• Mozc 2.18.2556.103 (ae6bbac)

Steps to reproduce

1. Install Mozc for Android
2. Open user dictionary tool
3. Add a new user dictionary entry
   • Word: test@example.com
   • Reading: め
   • Category: Suggestion only
4. Focus on an EditText.
5. Type め

Expected behavior

After the step 5, test@example.com is included in the candidate list.

Actual behavior

After the step 5, test@example.com not included in the candidate list.