谷歌拼音输入法，无候选词时，仅显示输入字符界面的问题

修改输入法为中文输入情况下，无候选词时，仅显示输入字符界面的问题；
修改输入字符为空时，候选试图仍不消失的bug。

PinyinIME.java类中修改候选试图是否显示的判断条件：

private void showCandidateWindow(boolean showComposingView) {
        if (mEnvironment.needDebug()) {
            Log.d(TAG, "Candidates window is shown. Parent = "
                    + mCandidatesContainer);
        }
        // mdy by cbl 2012-4-23 14:08:39
        //if no input word don't show the candidate view, no matter wether the CandidatesList is empty or not
        //if ComposingView is empty ,don't show the candidate view,in order to keep both ComposingView and candidateview show sync
        if (showComposingView) {
  setCandidatesViewShown(true);
} else {
  setCandidatesViewShown(false);
}