PagedView: fix pointer index out of range

Stacktrace:

java.lang.IllegalArgumentException: pointerIndex out of range
    at android.view.MotionEvent.nativeGetAxisValue(MotionEvent.java)
    at android.view.MotionEvent.getX(MotionEvent.java:2201)
    at com.android.launcher3.PagedView.onTouchEvent(PagedView.java:1557)
    at android.view.View.dispatchTouchEvent(View.java:11842)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3068)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2700)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3074)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2714)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3074)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2714)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3074)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2714)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3074)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2714)
    at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:3074)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2714)
    at com.android.internal.policy.DecorView.superDispatchTouchEvent(DecorView.java:464)
    at com.android.internal.policy.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1854)
    at android.app.Activity.dispatchTouchEvent(Activity.java:3292)
    at com.android.launcher3.Launcher.dispatchTouchEvent(Launcher.java:2781)
    at com.android.internal.policy.DecorView.dispatchTouchEvent(DecorView.java:426)
    at android.view.View.dispatchPointerEvent(View.java:12092)
    at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:5279)
    at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:5084)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4581)
    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4634)
    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4600)
    at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:4747)
    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4608)
    at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4804)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4581)
    at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4634)
    at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4600)
    at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4608)
    at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4581)
    at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:7259)
    at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:7233)
    at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:7176)
    at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:7431)
    at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
    at android.os.MessageQueue.nativePollOnce(MessageQueue.java)
    at android.os.MessageQueue.next(MessageQueue.java:325)
    at android.os.Looper.loop(Looper.java:147)
    at android.app.ActivityThread.main(ActivityThread.java:6733)
    at java.lang.reflect.Method.invoke(Method.java)
    at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:845)

Issue: SHIFTOS-SW-19
Change-Id: Idcab340d65ee2a4782052b4d1a9de73a886afef7
Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>