[llvm] [DirectX] Error handling improve in root signature metadata Parser (PR #149232)

[Chris B via llvm-commits]

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@@ -227,27 +218,23 @@ MDNode *MetadataBuilder::BuildStaticSampler(const StaticSampler &Sampler) {
   return MDNode::get(Ctx, Operands);
 }
 
-bool MetadataParser::parseRootFlags(LLVMContext *Ctx,
-                                    mcdxbc::RootSignatureDesc &RSD,
-                                    MDNode *RootFlagNode) {
-
+llvm::Error MetadataParser::parseRootFlags(mcdxbc::RootSignatureDesc &RSD,
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llvm-beanz wrote:

Since this source file is part of LLVM, we should just have a `using namespace llvm` declaration to avoid needing to explicitly qualify all the LLVM types and methods.

That also makes it more consistent since you have functions like this that are in types declared within the `llvm` namespace so you can inconsistently use unqualified or qualified names (see below where you call `make_error` but then `llvm::Error::success()`).

https://github.com/llvm/llvm-project/pull/149232