android4.0 判断是不是有语音麦克功能

在NavigationBarTablet.java类setSearchMode方法中判断是否有语音模块，若有则显示，没有则不显示。

privateResolveInfo getResolveInfo() {

         Intent intent =createVoiceSearchIntent();

         ResolveInfo ri = mContext.getPackageManager().

        resolveActivity(intent,PackageManager.MATCH_DEFAULT_ONLY);

         return ri;

}

protectedIntent createVoiceSearchIntent() {

         return newIntent(RecognizerIntent.ACTION_WEB_SEARCH);

}