Remove dead branches in Color.op_Equality

Color.op_Equality uses the common pattern for the name field of:
1. Return true on left is same instance as right.
2. Return false on left or right are null, since both null is
considered above
3. Do fuller equality test.

However since == is overloaded for string, step 1 is not as intended.
Since string == does the same logic as above anyway, the rest are just
three branches that will all return false.

Cut out these branches, and just use string == directly.

Also add test case for Color objects with equal, but not same-
instance, names, as this case isn't covered in current tests.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/System.Drawing.Primitives/tests/ColorTests.cs b/src/System.Drawing.Primitives/tests/ColorTests.cs
index 6bdcbc0d6a..3b5df94e40 100644
--- a/src/System.Drawing.Primitives/tests/ColorTests.cs
+++ b/src/System.Drawing.Primitives/tests/ColorTests.cs
@@ -493,6 +493,10 @@ namespace System.Drawing.Primitives.Tests
             yield return new object[] { Color.FromName("SomeName"), Color.FromName("SomeOtherName"), false };
 
             yield return new object[] { Color.FromArgb(0, 0, 0), default(Color), false };
+
+            string someNameConstructed = string.Join("", "Some", "Name");
+            Assert.NotSame("SomeName", someNameConstructed); // If this fails the above must be changed so this test is correct.
+            yield return new object[] {Color.FromName("SomeName"), Color.FromName(someNameConstructed), true};
         }
 
         [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework)] // desktop incorrectly does "name.Equals(name)" in Equals