tests: Move ManagedTracer test to its correct location

apis/Google.Cloud.Diagnostics.AspNetCore/Google.Cloud.Diagnostics.AspNetCore.Tests/Trace/CloudTraceExtensionTest.cs

@@ -75,20 +75,6 @@ public void CreateTraceHeaderContext_UseBackUpFunc()
             Assert.Equal(TraceHeaderContext.FromHeader(header).ToString(), headerContext.ToString());
         }
 
-        [Fact]
-        public void CreateManagedTracer()
-        {
-            var mockProvider = new Mock<IServiceProvider>();
-            var mockTracer = new Mock<IManagedTracer>();
-            string traceId = Guid.NewGuid().ToString("N");
-            mockTracer.Setup(p => p.GetCurrentTraceId()).Returns(traceId);
-            ContextTracerManager.SetCurrentTracer(mockTracer.Object);
-            var tracer = ManagedTracer.CreateDelegatingTracer(() => ContextTracerManager.GetCurrentTracer());
-            Assert.IsType<DelegatingTracer>(tracer);
-            Assert.Equal(traceId, tracer.GetCurrentTraceId());
-            mockTracer.Verify();
-        }
-
         [Fact]
         public void GetServiceCheckNotNull()
         {

apis/Google.Cloud.Diagnostics.Common/Google.Cloud.Diagnostics.Common.Tests/Trace/ManagedTracerTest.cs

@@ -0,0 +1,37 @@
+// Copyright 2021 Google LLC
+// 
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// 
+//     https://www.apache.org/licenses/LICENSE-2.0
+// 
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using Moq;
+using System;
+using Xunit;
+
+namespace Google.Cloud.Diagnostics.Common.Tests
+{
+    public class ManagedTracerTest
+    {
+        [Fact]
+        public void CreateDelegatingTracer()
+        {
+            var mockTracer = new Mock<IManagedTracer>();
+            string traceId = Guid.NewGuid().ToString("N");
+            mockTracer.Setup(p => p.GetCurrentTraceId()).Returns(traceId);
+
+            var tracer = ManagedTracer.CreateDelegatingTracer(() => mockTracer.Object);
+
+            Assert.IsType<DelegatingTracer>(tracer);
+            Assert.Equal(traceId, tracer.GetCurrentTraceId());
+            mockTracer.Verify();
+        }
+    }
+}