Increase test coverage for Exception.TargetSite (dotnet#50275)

* Increase test coverage for Exception.TargetSite

* Apply suggestions from code review

Co-authored-by: Stephen Toub <stoub@microsoft.com>

Co-authored-by: Stephen Toub <stoub@microsoft.com>

src/libraries/System.Runtime/tests/System/ExceptionTests.cs

@@ -61,7 +61,7 @@ public static void Exception_GetBaseException()
         }
 
         [Fact]
-        public static void Exception_TargetSite_Jit()
+        public static void Exception_TargetSite()
         {
             bool caught = false;
 
@@ -78,6 +78,32 @@ public static void Exception_TargetSite_Jit()
 
             Assert.True(caught);
         }
+
+        static void RethrowException()
+        {
+            try
+            {
+                ThrowException();
+            }
+            catch
+            {
+                throw;
+            }
+        }
+
+        [Fact]
+        public static void Exception_TargetSite_OtherMethod()
+        {
+            Exception ex = Assert.ThrowsAny<Exception>(() => ThrowException());
+            Assert.Equal(nameof(ThrowException), ex.TargetSite.Name);
+        }
+
+        [Fact]
+        public static void Exception_TargetSite_Rethrow()
+        {
+            Exception ex = Assert.ThrowsAny<Exception>(() => RethrowException());
+            Assert.Equal(nameof(ThrowException), ex.TargetSite.Name);
+        }
 
         [Fact]
         [ActiveIssue("https://github.com/mono/mono/issues/15140", TestRuntimes.Mono)]