[automerger skipped] CallStyle: add missing null check for icon am: e77705d241 -s ours

am skip reason: Merged-In I5d0773881171dd233411edc19d3988789dac4259 with SHA-1 bfc6a51b9b is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/26635008

Change-Id: Icc02122c0f138bec7354f268d6924f81600dd7fd
Signed-off-by: Automerger Merge Worker <[email protected]>