Fix visibility of several test methods (dotnet/corefx#36380)

Commit migrated from https://github.com/dotnet/corefx/commit/6038ddaa0ff66984fe157958ded2a2327ba1e743

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

@@ -522,7 +522,7 @@ class Flag
         }
 
         [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsInvokingStaticConstructorsSupported))]
-        static void TestingBindingFlags()
+        public static void TestingBindingFlags()
         {
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(ClassWithPrivateCtor), BindingFlags.Public | BindingFlags.Instance, null, null, CultureInfo.CurrentCulture));
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(ClassWithPrivateCtor), BindingFlags.Public | BindingFlags.Instance, null, new object[] { 1, 2, 3 }, CultureInfo.CurrentCulture));
@@ -553,7 +553,7 @@ static void TestingBindingFlags()
         }
 
         [Fact]
-        static void TestingBindingFlagsInstanceOnly()
+        public static void TestingBindingFlagsInstanceOnly()
         {
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(HasPublicCtor), default(BindingFlags), null, null, null));
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(HasPublicCtor), BindingFlags.NonPublic | BindingFlags.Instance, null, null, null));
@@ -575,7 +575,7 @@ static void TestingBindingFlagsInstanceOnly()
         }
 
         [Fact]
-        static void TestingBindingFlags1()
+        public static void TestingBindingFlags1()
         {
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(ClassWithPrivateCtor), BindingFlags.Public | BindingFlags.Instance, null, null, CultureInfo.CurrentCulture, null));
             Assert.Throws<MissingMethodException>(() => Activator.CreateInstance(typeof(ClassWithPrivateCtor), BindingFlags.Public | BindingFlags.Instance, null, new object[] { 1, 2, 3 }, CultureInfo.CurrentCulture, null));
@@ -586,7 +586,7 @@ static void TestingBindingFlags1()
 
         [Fact]
         [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework)]
-        static void TestingActivationAttributes()
+        public static void TestingActivationAttributes()
         {
             Assert.Throws<PlatformNotSupportedException>(() => Activator.CreateInstance(typeof(ClassWithIsTestedAttribute), null, new object[] { new object() }));
             Assert.Throws<PlatformNotSupportedException>(() => Activator.CreateInstance(typeof(ClassWithIsTestedAttribute), null, new object[] { new IsTestedAttribute(true) }));
@@ -599,7 +599,7 @@ static void TestingActivationAttributes()
         }
 
         [Fact]
-        static void TestingActivationAttributes1()
+        public static void TestingActivationAttributes1()
         {
             Activator.CreateInstance(typeof(ClassWithIsTestedAttribute), null, null);
             Activator.CreateInstance(typeof(ClassWithIsTestedAttribute), null, new object[] { });

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

@@ -106,7 +106,7 @@ public void CompareTo_Other_ReturnsExpected(bool b, object obj, int expected)
         [InlineData(true, "true")]
         [InlineData(false, 0)]
         [InlineData(false, "false")]
-        private void CompareTo_ObjectNotBool_ThrowsArgumentException(bool b, object obj)
+        public void CompareTo_ObjectNotBool_ThrowsArgumentException(bool b, object obj)
         {
             AssertExtensions.Throws<ArgumentException>(null, () => b.CompareTo(obj));
         }

src/libraries/System.Runtime/tests/System/Threading/WaitHandleTests.cs

@@ -251,7 +251,7 @@ yield return
 
         [Theory]
         [MemberData(nameof(SignalAndWait_MemberData))]
-        private static void SignalAndWait(
+        public static void SignalAndWait(
             WaitHandle toSignal,
             AutoResetEvent toWaitOn,
             Func<WaitHandle, WaitHandle, bool> callSignalAndWait,