Stop social update view from stealing focus.

ContactDetailFragmentCarousel was requesting focus to set the initial offset of
the HorizontalScrollView.  This was probably a hacky work around to get the
smoothScrollTo() method to work.

Instead of requesting focus, call scrollTo().  Before scrollTo() did not work
in the enableSwipe() method because HorizontalScrollView "clamp"s the offset
to the size of the width.  And the size of the width was calculated based on
mEnableSwipe flag in the onMeasure() method.  To fix it so scrollTo() works
within enableSwipe(), change the width calculation to also take into account
mCurrentPage which may be initialized to 1 instead of 0.

Old order
+ onMeasure() [mEnabledSwipe = false, width set for a single child]
+ enableSwipe() [mEnabledSwipe = true, width still set for a single child]
+ scrollTo() [page 1, fails because width set for a single child]

New logic
+ onMeasure() [mCurrentPage = 1, width set for 2 childs]
+ enableSwipe()
+ scrollTo() [page 1, suceeds]

Bug: 8157306
Change-Id: I3a693a0b3d43a68d251faea4b5805791f2316aaa