Remove redundant static fields to reduce memory usage in XamlTypeInvoker

[lindexi]

No description provided.

[pchaurasia14]

@lindexi - Do you have any benchmarks reports associated with this PR?

[lindexi]

@pchaurasia14 It just remote a static field. And I think it hard to write the benchmarks code.

[h3xds1nz]

@lindexi @pchaurasia14 The original code could be "faster" thanks to code-locality, the PR however saves few bytes in the class. If code-locality doesn't play a factor, both shall be equal in terms of performance.

In my opinion the perfect answer doesn't exist, code-gen itself is gonna be identical, Array.Empty<object>() returns a singleton, the code explosion already happened for object in some runtime lib, and in my opinion @lindexi's PR improves the code quality.

It is basically always going to boil down to this for a method that takes an arr as a param (obviously in case of the particular method in question, that would be already r9 register on x86_64)

mov rdx, 0x17664001eb8 ;immediate singleton ptr
mov rdx, [rdx] ;pass empty array ptr to func
call 0x00007ffbc4e90030 ;the function call

[MethodImpl(MethodImplOptions.NoInlining)]
private object[] EmptyMethod(object[] array)
{
    return suggestions;
}

[dipeshmsft]

Thank you @lindexi