Docs-change: clarification of LauncherApps.getApplicationInfo()

Staged at: go/dac-stage/reference/android/content/pm/LauncherApps.html#getApplicationInfo(java.lang.String, int, android.os.UserHandle)

Test: make ds-docs and output staged
Bug: 38024981
Change-Id: I9f256d675433457b7c85fa111ed87d1147f1f2bc