Revert "Roll Fuchsia SDK from 98ba6c8440c2 to b9dd8279f122"

This reverts commit 8ce5e80e.

Reason for revert:
It depended on #594419 which has been reverted, see bug.

Original change's description:
> Roll Fuchsia SDK from 98ba6c8440c2 to b9dd8279f122
> 
> 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_audio;luci.chromium.try:fuchsia_x64_cast_audio
> TBR=cr-fuchsia+bot@chromium.org
> TBR=sergeyu@chromium.org
> TBR=mmenke@chromium.org
> 
> Change-Id: I470f7f3a9b10ed9c31b40b02e1f5a01a36ff25f4
> Reviewed-on: https://chromium-review.googlesource.com/1246955
> Commit-Queue: Kevin Marshall <kmarshall@chromium.org>
> Reviewed-by: Kevin Marshall <kmarshall@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#594479}

TBR=kmarshall@chromium.org,cr-fuchsia+bot@chromium.org
Bug: 889839

Change-Id: I30b99003450fab8abdcc1c7751d264c5ae77a0aa
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: luci.chromium.try:fuchsia_arm64_cast_audio;luci.chromium.try:fuchsia_x64_cast_audio
Reviewed-on: https://chromium-review.googlesource.com/1249105Reviewed-by: Hans Wennborg <hans@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594681}

build/fuchsia/linux.sdk.sha1

-b9dd8279f122d4d9718e66d5b9bd974b18924d57
\ No newline at end of file
+98ba6c8440c2afb334433de9bb901a0f97efe1e1
\ No newline at end of file

build/fuchsia/mac.sdk.sha1

-ebbe4babd77b3b6a943ebc24daeeb48b1a2468d5
\ No newline at end of file
+bd8834505d919018dd7ffdc5fa42eb04616ca9f5
\ No newline at end of file

net/base/network_change_notifier_fuchsia_unittest.cc

@@ -146,13 +146,8 @@ class FakeNetstack : public fuchsia::netstack::Netstack {
   void GetStats(uint32_t nicid, GetStatsCallback callback) override {}
   void GetAggregateStats(GetAggregateStatsCallback callback) override {}
   void SetInterfaceStatus(uint32_t nicid, bool enabled) override {}
-  void AddEthernetDevice(
-      fidl::StringPtr topological_path,
-      fidl::InterfaceHandle<::zircon::ethernet::Device> device) override {}
-  void StartRouteTableTransaction(
-      fidl::InterfaceRequest<fuchsia::netstack::RouteTableTransaction>
-          routeTableTransaction,
-      StartRouteTableTransactionCallback callback) override {}
+  void SetRouteTable(
+      ::fidl::VectorPtr<fuchsia::netstack::RouteTableEntry> rt) override {}
   void SetInterfaceAddress(uint32_t nicid,
                            fuchsia::netstack::NetAddress addr,
                            uint8_t prefixLen,