Fix NewApi warnings for Looper.myLooper().getQueue()

Uses an equivalent call available from API level 1.

Bug: 762550
Change-Id: I06bb2dc42f7126cbe235cf4745fd35b29300abfa
Reviewed-on: https://chromium-review.googlesource.com/652594Reviewed-by: Peter Wen <wnwen@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#499981}

base/android/java/src/org/chromium/base/JavaHandlerThread.java

@@ -56,7 +56,7 @@ public class JavaHandlerThread {
     @CalledByNative
     private void stopOnThread(final long nativeThread) {
         nativeStopThread(nativeThread);
-        MessageQueue queue = mThread.getLooper().getQueue();
+        MessageQueue queue = Looper.myQueue();
         // Add an idle handler so that the thread cleanup code can run after the message loop has
         // detected an idle state and quit properly.
         // This matches the behavior of base::Thread in that it will keep running non-delayed posted

base/android/java/src/org/chromium/base/SystemMessageHandler.java

@@ -41,7 +41,7 @@ class SystemMessageHandler extends Handler {
     protected SystemMessageHandler(long messagePumpDelegateNative, long messagePumpNative) {
         mMessagePumpDelegateNative = messagePumpDelegateNative;
         mMessagePumpNative = messagePumpNative;
-        Looper.myLooper().getQueue().addIdleHandler(mIdleHandler);
+        Looper.myQueue().addIdleHandler(mIdleHandler);
     }
 
     @Override
@@ -74,7 +74,7 @@ class SystemMessageHandler extends Handler {
     private void removeAllPendingMessages() {
         removeMessages(SCHEDULED_WORK);
         removeMessages(DELAYED_SCHEDULED_WORK);
-        Looper.myLooper().getQueue().removeIdleHandler(mIdleHandler);
+        Looper.myQueue().removeIdleHandler(mIdleHandler);
     }
 
     private Message obtainAsyncMessage(int what) {