Fix some flaky tests.

In tests, we create many instances of LatinIME, but we never
destroy them. That means we never close the dictionaries nor
the handlers.
This change calls onDestroy, which closes all dictionaries, and
adds some code to finish the handlers.

Change-Id: I942517a2a940c54256b08763f6b38f5b55809f55

java/src/com/android/inputmethod/compat/LooperCompatUtils.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.inputmethod.compat;
+
+import android.os.Looper;
+
+import java.lang.reflect.Method;
+
+/**
+ * Helper to call Looper#quitSafely, which was introduced in API
+ * level 18 (Build.VERSION_CODES.JELLY_BEAN_MR2).
+ *
+ * In unit tests, we create lots of instances of LatinIME, which means we need to clean up
+ * some Loopers lest we leak file descriptors. In normal use on a device though, this is never
+ * necessary (although it does not hurt).
+ */
+public final class LooperCompatUtils {
+    private static final Method METHOD_quitSafely = CompatUtils.getMethod(
+            Looper.class, "quitSafely");
+
+    public static void quitSafely(final Looper looper) {
+        if (null != METHOD_quitSafely) {
+            CompatUtils.invoke(looper, null /* default return value */, METHOD_quitSafely);
+        } else {
+            looper.quit();
+        }
+    }
+}

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

@@ -635,6 +635,11 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
         super.onDestroy();
     }
 
+    @UsedForTesting
+    public void recycle() {
+        mInputLogic.recycle();
+    }
+
     @Override
     public void onConfigurationChanged(final Configuration conf) {
         // If orientation changed while predicting, commit the change

java/src/com/android/inputmethod/latin/inputlogic/InputLogic.java

@@ -148,6 +148,17 @@ public final class InputLogic {
         mInputLogicHandler.reset();
     }
 
+    // Normally this class just gets out of scope after the process ends, but in unit tests, we
+    // create several instances of LatinIME in the same process, which results in several
+    // instances of InputLogic. This cleans up the associated handler so that tests don't leak
+    // handlers.
+    public void recycle() {
+        final InputLogicHandler inputLogicHandler = mInputLogicHandler;
+        mInputLogicHandler = InputLogicHandler.NULL_HANDLER;
+        inputLogicHandler.destroy();
+        mSuggest.mDictionaryFacilitator.closeDictionaries();
+    }
+
     /**
      * React to a string input.
      *

java/src/com/android/inputmethod/latin/inputlogic/InputLogicHandler.java

@@ -20,6 +20,7 @@ import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.Message;
 
+import com.android.inputmethod.compat.LooperCompatUtils;
 import com.android.inputmethod.latin.InputPointers;
 import com.android.inputmethod.latin.LatinIME;
 import com.android.inputmethod.latin.Suggest;
@@ -80,6 +81,12 @@ class InputLogicHandler implements Handler.Callback {
         mNonUIThreadHandler.removeCallbacksAndMessages(null);
     }
 
+    // In unit tests, we create several instances of LatinIME, which results in several instances
+    // of InputLogicHandler. To avoid these handlers lingering, we call this.
+    public void destroy() {
+        LooperCompatUtils.quitSafely(mNonUIThreadHandler.getLooper());
+    }
+
     /**
      * Handle a message.
      * @see android.os.Handler.Callback#handleMessage(android.os.Message)

tests/src/com/android/inputmethod/latin/InputTestsBase.java

@@ -213,13 +213,18 @@ public class InputTestsBase extends ServiceTestCase<LatinIMEForTests> {
 
     @Override
     protected void tearDown() throws Exception {
+        mLatinIME.onFinishInputView(true);
+        mLatinIME.onFinishInput();
+        runMessages();
         mLatinIME.mHandler.removeAllMessages();
         setBooleanPreference(Settings.PREF_BIGRAM_PREDICTIONS, mPreviousBigramPredictionSettings,
                 true /* defaultValue */);
         setStringPreference(Settings.PREF_AUTO_CORRECTION_THRESHOLD, mPreviousAutoCorrectSetting,
                 DEFAULT_AUTO_CORRECTION_THRESHOLD);
         setDebugMode(false);
+        mLatinIME.recycle();
         super.tearDown();
+        mLatinIME = null;
     }
 
     // We need to run the messages added to the handler from LatinIME. The only way to do