Roll Fuchsia SDK from 3697400dc0b6 to 4cb6cfe20aa2

The AutoRoll server is located here: https://autoroll.skia.org/r/fuchsia-sdk-chromium-autoroll

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


CQ_INCLUDE_TRYBOTS=luci.chromium.try:fuchsia-arm64-cast;luci.chromium.try:fuchsia-x64-cast
TBR=cr-fuchsia+bot@chromium.org

Change-Id: I8a0bd0021b2ab23c0154a3a668bf018cc8df5322
Reviewed-on: https://chromium-review.googlesource.com/c/1393413Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#619515}

build/fuchsia/linux.sdk.sha1

-3697400dc0b66d69e8bb1544147bf387ae4e5a81
+4cb6cfe20aa2144b34d051ee31306969be7582c7
\ No newline at end of file

build/fuchsia/mac.sdk.sha1

-fa7ae7dc8664d4089fd890b79358d1db5cfb7fa1
+ece0fa0dc069c87a2ce7636fc4b170de33642d05
\ No newline at end of file