switch ResearchLogger output to json.

use multiple logging files, clean up internal nested class structure.

multi-project commit with I1813b6710ef586d96cf8936662f58b870040d6e5

Bug: 6188932
Change-Id: I438790e28f74747c4c1a48a20c1942a0fd818b6c

java/proguard.flags

@@ -37,13 +37,7 @@
 }
 
 -keep class com.android.inputmethod.latin.ResearchLogger {
-  void setLogFileManager(...);
-  void clearAll();
-  com.android.inputmethod.latin.ResearchLogger$LogFileManager getLogFileManager();
-}
-
--keep class com.android.inputmethod.latin.ResearchLogger$LogFileManager {
-  java.lang.String getContents();
+  void flush();
 }
 
 -keep class com.android.inputmethod.keyboard.KeyboardLayoutSet$Builder {

java/src/com/android/inputmethod/latin/LatinIME.java

@@ -388,7 +388,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         mPrefs = prefs;
         LatinImeLogger.init(this, prefs);
         if (ProductionFlag.IS_EXPERIMENTAL) {
-            ResearchLogger.init(this, prefs);
+            ResearchLogger.getInstance().init(this, prefs);
         }
         InputMethodManagerCompatWrapper.init(this);
         SubtypeSwitcher.init(this);
@@ -643,6 +643,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                     + ((editorInfo.inputType & InputType.TYPE_TEXT_FLAG_CAP_WORDS) != 0));
         }
         if (ProductionFlag.IS_EXPERIMENTAL) {
+            ResearchLogger.getInstance().start();
             ResearchLogger.latinIME_onStartInputViewInternal(editorInfo, mPrefs);
         }
         if (InputAttributes.inPrivateImeOptions(null, NO_MICROPHONE_COMPAT, editorInfo)) {
@@ -724,6 +725,9 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         super.onFinishInput();
 
         LatinImeLogger.commit();
+        if (ProductionFlag.IS_EXPERIMENTAL) {
+            ResearchLogger.getInstance().stop();
+        }
 
         KeyboardView inputView = mKeyboardSwitcher.getKeyboardView();
         if (inputView != null) inputView.closing();
@@ -1233,9 +1237,7 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         mLastKeyTime = when;
 
         if (ProductionFlag.IS_EXPERIMENTAL) {
-            if (ResearchLogger.sIsLogging) {
-                ResearchLogger.getInstance().logKeyEvent(primaryCode, x, y);
-            }
+            ResearchLogger.latinIME_onCodeInput(primaryCode, x, y);
         }
 
         final KeyboardSwitcher switcher = mKeyboardSwitcher;