Don't unnecessarily set LayoutParams on children

Setting LayoutParams on children triggers requestLayout
which can be expensive and result in significantly lower
framerate for children layouts that don't need it. When
requestLayout method is invoked the needToMeasure boolean
will be true, this is what we'd like to avoid unless
it is actually needed.

BUG: https://code.google.com/p/android/issues/detail?id=72733



Change-Id: Id5d8f3431b5f943b1279eae41ee43d32a99514fc
Signed-off-by: Jacob Abrams <satur9nine@gmail.com>