Fix rounding error related to autoSize

setupAutoSize fills in the possible text sizes that can be generated
between a min and max value. In order to do that, it counts the number
of steps starting from minSize until maxSize. However, while counting
it rounds the initial value, which causes rounding error at the final
step.

Test: Change system font scale to 1.1 via
      adb shell settings put system font_scale 1.1
Test: atest android.widget.cts.TextViewTest

Bug: 73917559
Bug: 75266270
Change-Id: I61811db28ef01262bd48f5042d783d75c71c3614
(cherry picked from commit db86a6b0)