Fuzzer assert in GradientShaderBase4fContext::TSampler

Similar to https://codereview.chromium.org/2472763002, we also need to
clamp the tiled value in kRepeat mode, to avoid snapping to 1.0f.

R=reed@google.com,herb@google.com
BUG=skia:5975

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=5079

Change-Id: I8fdac36c0d112d5eb76e47c3e4156a79a4d13b36
Reviewed-on: https://skia-review.googlesource.com/5079
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
1 file changed