Better isolate ResearchLogging data

Calls to LatinIME#onStartInputViewInternal log important information
about the context in which an IME is used.  This is reported as a
single LogStatement.  Previously, this was not placed into a separate
LogUnit, and was mixed in with general word data.  This change wraps
this LogStatement in its own LogUnit.

Change-Id: I0fecd41c8a1de622a764cc4b5d6902336697046c

java/src/com/android/inputmethod/research/ResearchLogger.java

@@ -1089,6 +1089,9 @@ public class ResearchLogger implements SharedPreferences.OnSharedPreferenceChang
                         Build.DISPLAY, Build.MODEL, prefs, versionCode, versionName,
                         OUTPUT_FORMAT_VERSION, IS_LOGGING_EVERYTHING,
                         researchLogger.isDevTeamBuild());
+                // Commit the logUnit so the LatinImeOnStartInputViewInternal event is in its own
+                // logUnit at the beginning of the log.
+                researchLogger.commitCurrentLogUnit();
             } catch (final NameNotFoundException e) {
                 Log.e(TAG, "NameNotFound", e);
             }