Convert the remaining FP tests to golden outputs.

(Removed one test, SkSLFPSwitchWithMultipleReturnsInside, because it was
redundant with existing tests.)

Change-Id: I1bfc069babdb5eb0cc515f195c3a2e307bb5871a
Bug: skia:10694
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/319029
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
57 files changed