Prefix type names with global and use static TypeSyntax and NameSyntax instead of Parse(Type)Name

[jtschuster]

Fixes #90299

There were a few places where we would use the type names without the global:: prefix that causes issues when there is another "System" symbol in the context. To avoid this, we can use a static TypeSyntax and NameSyntax for well-known types instead of calling ParseTypeName or ParseName and remembering to prefix "global::". Though of course now we need to remember to use these instead of ParseTypeName...

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Issue Details

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Fixes #90299

There were a few places where we would use the type names without the global:: prefix that causes issues when there is another "System" symbol in the context. To avoid this, we can use a static TypeSyntax and NameSyntax for well-known types instead of calling ParseTypeName or ParseName and remembering to prefix "global::". Though of course now we need to remember to use these instead of ParseTypeName...

Author:	jtschuster
Assignees:	-
Labels:	area-System.Runtime.InteropServices
Milestone:	-

[jtschuster]

Looks like there's a few I missed, like Span and ThrowForHR.

[jtschuster]

Still some code cleanup that can be done, but the generated code looks good and this should probably make it into 8. I'll do the follow up for 9.

[IDisposable]

LGTM

[jtschuster]

Failures are known