Timesync commissioner: Fix TrustedTimeSource. (#28284)

Turns out I never set it, and the tests didn't catch it because I
was so preocupied with validating the state machine that I never
checked the actual values. Whoops.

Test: Please see test included in PR.

src/controller/CHIPDeviceController.cpp

@@ -2678,7 +2678,7 @@ void DeviceCommissioner::PerformCommissioningStep(DeviceProxy * proxy, Commissio
             return;
         }
         TimeSynchronization::Commands::SetTrustedTimeSource::Type request;
-        request.trustedTimeSource.SetNull();
+        request.trustedTimeSource = params.GetTrustedTimeSource().Value();
         SendCommand(proxy, request, OnBasicSuccess, OnBasicFailure, endpoint, timeout);
         break;
     }

src/python_testing/TestCommissioningTimeSync.py

@@ -117,7 +117,8 @@ async def commission_stages(self, time_zone: bool, dst: bool, default_ntp: bool,
             self.commissioner.SetTimeZone(offset=3600, validAt=0)
         if dst:
             six_months = 1.577e+13  # in us
-            self.commissioner.SetDSTOffset(offset=3600, validStarting=0, validUntil=utc_time_in_matter_epoch() + int(six_months))
+            dst_valid_until = utc_time_in_matter_epoch() + int(six_months)
+            self.commissioner.SetDSTOffset(offset=3600, validStarting=0, validUntil=dst_valid_until)
         if default_ntp:
             self.commissioner.SetDefaultNTP("fe80::1")
         if trusted_time_source:
@@ -130,7 +131,6 @@ async def commission_stages(self, time_zone: bool, dst: bool, default_ntp: bool,
         should_set_default_ntp = bool(self.supports_default_ntp and default_ntp)
         should_set_trusted_time = bool(self.supports_trusted_time_source and trusted_time_source)
 
-        print(f'{should_set_time_zone} {should_set_dst} {should_set_default_ntp} {should_set_trusted_time}')
         asserts.assert_equal(self.commissioner.CheckStageSuccessful(kConfigureTimeZone),
                              should_set_time_zone, 'Incorrect value for time zone stage check')
         asserts.assert_equal(self.commissioner.CheckStageSuccessful(kConfigureDSTOffset),
@@ -140,6 +140,29 @@ async def commission_stages(self, time_zone: bool, dst: bool, default_ntp: bool,
         asserts.assert_equal(self.commissioner.CheckStageSuccessful(kConfigureTrustedTimeSource),
                              should_set_trusted_time, 'Incorrect value for kConfigureTrustedTimeSource stage')
 
+        if should_set_time_zone:
+            received = await self.read_single_attribute_check_success(cluster=Clusters.TimeSynchronization, attribute=Clusters.TimeSynchronization.Attributes.TimeZone)
+            expected = [Clusters.TimeSynchronization.Structs.TimeZoneStruct(offset=3600, validAt=0)]
+            asserts.assert_equal(received, expected, "Time zone was not correctly set by commissioner")
+
+        if should_set_dst:
+            received = await self.read_single_attribute_check_success(cluster=Clusters.TimeSynchronization, attribute=Clusters.TimeSynchronization.Attributes.DSTOffset)
+            expected = [Clusters.TimeSynchronization.Structs.DSTOffsetStruct(
+                offset=3600, validStarting=0, validUntil=dst_valid_until)]
+            asserts.assert_equal(received, expected, "DST was not set correctly by the commissioner")
+
+        if should_set_trusted_time:
+            fabric_idx = await self.read_single_attribute_check_success(cluster=Clusters.OperationalCredentials, attribute=Clusters.OperationalCredentials.Attributes.CurrentFabricIndex, dev_ctrl=self.commissioner)
+            received = await self.read_single_attribute_check_success(cluster=Clusters.TimeSynchronization, attribute=Clusters.TimeSynchronization.Attributes.TrustedTimeSource)
+            expected = Clusters.TimeSynchronization.Structs.TrustedTimeSourceStruct(
+                fabricIndex=fabric_idx, nodeID=self.commissioner.nodeId, endpoint=0)
+            asserts.assert_equal(received, expected, "Trusted Time source was not set properly")
+
+        if should_set_default_ntp:
+            received = await self.read_single_attribute_check_success(cluster=Clusters.TimeSynchronization, attribute=Clusters.TimeSynchronization.Attributes.DefaultNTP)
+            expected = "fe80::1"
+            asserts.assert_equal(received, expected, "Default NTP was not set properly")
+
     @async_test_body
     async def test_CommissioningAllBasic(self):
         # We want to assess all combos (ie, all flags in the range of 0b0000 to 0b1111)