Remove the synchronization

All of the callbacks happen on the same thread; no need to
synchronize. Also move away from TimerTask and use Handler to post
the termination callback.

Change-Id: If684e29686f2c7557cc56057c7f1ec6a1dfd3bcb
diff --git a/src/com/android/telecomm/ThreadUtil.java b/src/com/android/telecomm/ThreadUtil.java
new file mode 100644
index 0000000..b826f58
--- /dev/null
+++ b/src/com/android/telecomm/ThreadUtil.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright 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.telecomm;
+
+import android.os.Looper;
+import android.util.Log;
+
+/**
+ * A utility class which helps organize callers' threads. This class cannot be instantiated; callers
+ * should use the static methods.
+ */
+public final class ThreadUtil {
+    private static final String TAG = ThreadUtil.class.getSimpleName();
+
+    private ThreadUtil() {}
+
+    /** @return whether this method is being called from the main (UI) thread. */
+    public static boolean isOnMainThread() {
+        return Looper.getMainLooper() == Looper.myLooper();
+    }
+
+    /**
+     * Checks that this is being executed on the main thread. If not, a message is logged at
+     * WTF-level priority.
+     */
+    public static void checkOnMainThread() {
+        if (!isOnMainThread()) {
+            Log.wtf(TAG, "Must be on the main thread!", new IllegalStateException());
+        }
+    }
+
+    /**
+     * Checks that this is not being executed on the main thread. If so, a message is logged at
+     * WTF-level priority.
+     */
+    public static void checkNotOnMainThread() {
+        if (isOnMainThread()) {
+            Log.wtf(TAG, "Must not be on the main thread!", new IllegalStateException());
+        }
+    }
+}