CMFileManager: Fix the crash when the search file name includes mutiple white spaces.

    When the file name include mutiple white spaces and it fit for the search condition.
The highlight logical call Html.fromHtml will convert mutiple white spaces to one white
space (For example, the file name is "A  .mp3", after conver it will change to "A .mp3"),
the span length will less than the orginal file name. When call setSpan,
it will throw IndexOutOfBoundsException.

Change-Id: I00e26464427538de8f5f85ac8d6d009493767b1e