docs: M Preview 2 - release notes

<h2 id="release-notes">Release Notes</h2>

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      alt=""/>M Developer Preview, Revision 2</a> <em>(Month 2015)</em>

      alt=""/>M Developer Preview 2</a> <em>(July 2015)</em>

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    <dl>

    <dt>Fix Category 1</dt>

    <dt>API Name Changes:</dt>

    <dd>

      <ul>

        <li>Fixed issue X.</li>

        <li>Fixed issue Y.</li>

        <li>Fixed issue Z.</li>

      </ul>

    </dd>

    <dt>Fix Category 2</dt>

    <dd>

      <ul>

        <li>Fixed issue X.</li>

        <li>Fixed issue Y.</li>

        <li>Fixed issue Z.</li>

        <li>Moved the {@code android.app.AssistContent} class to a different package,

          {@code android.app.assist.AssistContent} in the Assist API.</li>

        <li>Moved the {@code android.app.AssistStructure} class to a different package,

          {@code android.app.assist.AssistStructure} in the Assist API.</li>

        <li>Replaced the {@code ScanResult.PasspointNetwork} property with the

          {@code ScanResult.isPasspointNetwork()} method for HotSpot 2.0 support.</li>

        <li>Replaced the {@code InputDevice.hasMic()} method with {@code InputDevice.hasMicrophone()}

          for the Audio API.</li>

        <li>Renamed the {@code View.OnStylusButtonPressListener} class to

          {@code View.OnContextClickListener} for Bluetooth Stylus support.</li>

        <li>Renamed the {@code GestureDetector.OnStylusButtonPressListener} class to

          {@code GestureDetector.OnContextClickListener} for Bluetooth Stylus support.</li>

        <li>Renamed the {@code android.app.usage.NetworkUsageStats} class to

          {@code android.app.usage.NetworkStats}.</li>

        <li>Renames the {@code android.app.usage.NetworkUsageStats.Bucket} class to

          {@code android.app.usage.NetworkStats.Bucket}.</li>

      </ul>

    </dd>

    </dl>

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    <img src="{@docRoot}assets/images/triangle-opened.png" class="toggle-content-img"

      alt=""/>M Developer Preview, Revision 1</a> <em>(May 2015)</em>

    <img src="{@docRoot}assets/images/triangle-closed.png" class="toggle-content-img"

      alt=""/>M Developer Preview 1</a> <em>(May 2015)</em>

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