Utility class help you to drop Fragment state before it's being restored.

FragmentStateUtil.java

package your.packagename;

import android.app.Activity;
import android.os.Bundle;

import java.lang.reflect.Array;
import java.lang.reflect.Field;

/**
 * Prevent Fragment being restored in {@link Activity#onCreate(Bundle)}.
 *
 * @see <a href="https://stackoverflow.com/questions/15519214/prevent-fragment-recovery-in-android">https://stackoverflow.com/questions/15519214/prevent-fragment-recovery-in-android</a>
 */
public class FragmentStateUtil {
    private final String FRAGMENTS_TAG;
    private final Bundle mBundleSavedInstanceState;
    private final FragmentManagerState mFragmentManagerState;

    /**
     * <span style="font-weight: bold;">NOTE:</span> Do it <span style="font-weight: bold;">BEFORE</span>
     * {@linkplain android.app.Activity#onCreate(Bundle) super.onCreate(Bundle)}
     *
     * @param activity
     * @param savedInstanceState
     * @throws NoSuchFieldException
     * @throws IllegalAccessException
     */
    public FragmentStateUtil(Activity activity, Bundle savedInstanceState) throws NoSuchFieldException, IllegalAccessException {
        this.FRAGMENTS_TAG = getFragmentsTagString(activity);
        if (FRAGMENTS_TAG == null) {
            throw new IllegalStateException("Can't find FRAGMENTS_TAG in class " + activity.getClass().getName());
        }
        this.mBundleSavedInstanceState = savedInstanceState;
        this.mFragmentManagerState = new FragmentManagerState(savedInstanceState.getParcelable(FRAGMENTS_TAG));
    }

    /**
     * Find value of field {@code FRAGMENTS_TAG} from Activity, this field exists in these classes:<br/>
     * <ol>
     * <li>{@link android.app.Activity#FRAGMENTS_TAG}</li>
     * <li>{@link android.support.v4.app.FragmentActivity#FRAGMENTS_TAG}</li>
     * </ol>
     * You may not need this, but just in case.
     *
     * @param activity
     * @return Value of {@code FRAGMENTS_TAG}, {@code null} if not found.
     * @throws IllegalAccessException
     */
    public static String getFragmentsTagString(Activity activity) throws IllegalAccessException {
        Field lFieldStrFragmentsTag = null;
        for (Class lClass = activity.getClass(); !lClass.equals(Object.class); ) {
            try {
                lFieldStrFragmentsTag = lClass.getDeclaredField("FRAGMENTS_TAG");
                break;
            } catch (NoSuchFieldException ignore) {
            }
            lClass = lClass.getSuperclass();
        }
        if (lFieldStrFragmentsTag == null) return null;
        lFieldStrFragmentsTag.setAccessible(true);
        return (String) lFieldStrFragmentsTag.get(activity);
    }

    /**
     * Drop all fragment's state.
     */
    public void dropFragmentState() {
        mBundleSavedInstanceState.remove(FRAGMENTS_TAG);
    }

    /**
     * Drop fragment state by fragment ID.
     *
     * @param fragmentId
     * @return Dropped or not.
     * @throws NoSuchFieldException
     * @throws IllegalAccessException
     * @see android.app.FragmentTransaction#add(int, android.app.Fragment)
     * @see android.app.FragmentTransaction#add(int, android.app.Fragment, String)
     */
    public boolean dropFragmentState(int fragmentId) throws NoSuchFieldException, IllegalAccessException {
        return mFragmentManagerState.dropFragmentState(fragmentId);
    }

    /**
     * Drop fragment state by fragment tag.
     *
     * @param tag
     * @return Dropped or not.
     * @throws NoSuchFieldException
     * @throws IllegalAccessException
     * @see android.app.FragmentTransaction#add(android.app.Fragment, String)
     * @see android.app.FragmentTransaction#add(int, android.app.Fragment, String)
     */
    public boolean dropFragmentState(String tag) throws NoSuchFieldException, IllegalAccessException {
        return mFragmentManagerState.dropFragmentState(tag);
    }

    /**
     * Drop fragment state by class name.
     *
     * @param klass
     * @return How many fragment state dropped, {@code 0} is possible.
     * @throws NoSuchFieldException
     * @throws IllegalAccessException
     */
    public int dropFragmentState(Class klass) throws NoSuchFieldException, IllegalAccessException {
        return mFragmentManagerState.dropFragmentState(klass);
    }
}

/**
 * @see android.app.FragmentManager.FragmentManagerState
 */
final class FragmentManagerState {
    private final Class CLASS_FragmentManagerState;
    private final Field FIELD_mActive;
    private final Field FIELD_mAdded;

    private final Object mInstance;

    public FragmentManagerState(Object fragmentManagerState) throws NoSuchFieldException {
        if (fragmentManagerState == null) throw new NullPointerException("fragmentManagerState");
        mInstance = fragmentManagerState;
        CLASS_FragmentManagerState = mInstance.getClass();
        FIELD_mActive = CLASS_FragmentManagerState.getDeclaredField("mActive");
        FIELD_mActive.setAccessible(true);
        FIELD_mAdded = CLASS_FragmentManagerState.getDeclaredField("mAdded");
        FIELD_mAdded.setAccessible(true);
    }

    public FragmentState[] getActive() throws IllegalAccessException, NoSuchFieldException {
        Object lObjectArrFragmentState = FIELD_mActive.get(mInstance);
        FragmentState[] lFragmentStateArray = new FragmentState[Array.getLength(lObjectArrFragmentState)];
        for (int i = 0; i < lFragmentStateArray.length; i++) {
            lFragmentStateArray[i] = new FragmentState(Array.get(lObjectArrFragmentState, i));
        }
        return lFragmentStateArray;
    }

    public void setActive(FragmentState[] fragmentStates) throws IllegalAccessException {
        if (fragmentStates == null || fragmentStates.length < 1) {
            return;
        }
        Object lObjectArrFragmentState = Array.newInstance(fragmentStates[0].getRealClass(), fragmentStates.length);
        for (int i = 0; i < fragmentStates.length; i++) {
            Array.set(lObjectArrFragmentState, i, fragmentStates[i].getRealInstance());
        }
        FIELD_mActive.set(mInstance, lObjectArrFragmentState);
    }

    public int[] getAdded() throws IllegalAccessException {
        return (int[]) FIELD_mAdded.get(mInstance);
    }

    public void setAdded(int[] added) throws IllegalAccessException {
        FIELD_mAdded.set(mInstance, added);
    }

    public boolean dropFragmentState(final int fragmentId) throws NoSuchFieldException, IllegalAccessException {
        FragmentState[] lArrFragmentState = getActive();
        for (int i = 0, lnLength = lArrFragmentState.length; i < lnLength; i++) {
            FragmentState lFragmentState = lArrFragmentState[i];
            if (lFragmentState.getFragmentId() == fragmentId) {
                dropFragmentStateByIndex(i);
                return true;
            }
        }
        return false;
    }

    public boolean dropFragmentState(final String tag) throws NoSuchFieldException, IllegalAccessException {
        FragmentState[] lArrFragmentState = getActive();
        for (int i = 0, lnLength = lArrFragmentState.length; i < lnLength; i++) {
            FragmentState lFragmentState = lArrFragmentState[i];
            if (lFragmentState.getTag().equals(tag)) {
                dropFragmentStateByIndex(i);
                return true;
            }
        }
        return false;
    }

    public int dropFragmentState(final Class klass) throws NoSuchFieldException, IllegalAccessException {
        FragmentState[] lArrFragmentState = getActive();
        int lnFragmentStateDropped = 0;
        for (int i = 0, lnLength = lArrFragmentState.length; i < lnLength; i++) {
            FragmentState lFragmentState = lArrFragmentState[i];
            if (lFragmentState.getClassName().equals(klass.getName())) {
                dropFragmentStateByIndex(i);
                lnFragmentStateDropped++;
                lArrFragmentState = getActive();
                lnLength = lArrFragmentState.length;
                i--;
            }
        }
        return lnFragmentStateDropped;
    }

    private void dropFragmentStateByIndex(int index) throws NoSuchFieldException, IllegalAccessException {
        FragmentState[] lArrFragmentState = getActive();
        int[] lnArrAdded = getAdded();
        FragmentState[] lArrFragmentStateNew = new FragmentState[lArrFragmentState.length - 1];
        int[] lnArrAddedNew = new int[lnArrAdded.length - 1];

        for (int i = 0, iNew = 0; i < lArrFragmentState.length; i++) {
            if (i == index) continue;
            lArrFragmentStateNew[iNew] = lArrFragmentState[i];
            lnArrAddedNew[iNew] = lnArrAdded[i];
            iNew++;
        }
        setActive(lArrFragmentStateNew);
        setAdded(lnArrAddedNew);
    }
}

/**
 * @see android.app.Fragment.FragmentState
 */
final class FragmentState {
    private final Class CLASS_FragmentState;
    private final Field FIELD_mFragmentId;
    private final Field FIELD_mTag;
    private final Field FIELD_mClassName;

    private final Object mInstance;

    public FragmentState(Object fragmentState) throws NoSuchFieldException {
        if (fragmentState == null) throw new NullPointerException("fragmentState");
        mInstance = fragmentState;
        CLASS_FragmentState = mInstance.getClass();
        FIELD_mFragmentId = CLASS_FragmentState.getDeclaredField("mFragmentId");
        FIELD_mFragmentId.setAccessible(true);
        FIELD_mTag = CLASS_FragmentState.getDeclaredField("mTag");
        FIELD_mTag.setAccessible(true);
        FIELD_mClassName = CLASS_FragmentState.getDeclaredField("mClassName");
        FIELD_mClassName.setAccessible(true);
    }

    public Class getRealClass() {
        return CLASS_FragmentState;
    }

    public Object getRealInstance() {
        return mInstance;
    }

    public int getFragmentId() throws IllegalAccessException {
        return FIELD_mFragmentId.getInt(mInstance);
    }

    public String getTag() throws IllegalAccessException {
        return (String) FIELD_mTag.get(mInstance);
    }

    public String getClassName() throws IllegalAccessException {
        return (String) FIELD_mClassName.get(mInstance);
    }
}