Merge "Clean up String.indexOf() intrinsics." am: 479ac58aa2
am: 906a81a1d2

* commit '906a81a1d2312a3f6d3f43d10bf0431e47b38b43':
  Clean up String.indexOf() intrinsics.

Change-Id: Ibefcd247cec9a43bbe27415de9fbd072e702f5e0