benefits icon part of background, not float

The separate icon floating left made the benefit text not request a
width, so the benefits column width was determined by the h2 "made by
people like you" heading and a short h2 could clip big numbers.

Now the icon is part of the background for the text div, and the column
width is the larger of h2 heading and benefits.

Bug: 48909
Change-Id: Iaf5fb1ccb4f50d34cad8a29b2bdd8f5b267ef008
(cherry picked from commit 24558b5a27d76ea49e06dce705e16e6710add3b7)