Revert the namer changes.

This CL reverts the changes to use the top level namer in the various
backends. This is causing issues when rolling into Dawn in the case
where the tint generator is used to create SPIR-V which is sent to
SPIRV-Cross but then generator and inspector aren't used. The entry
points end up being incorrect as SPIRV-Cross gets the renamed entry
points.

Change-Id: I4749e1d773f2bd9edcce83e63555f07a443d5ca5
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/37342
Reviewed-by: dan sinclair <dsinclair@chromium.org>
Commit-Queue: dan sinclair <dsinclair@chromium.org>
diff --git a/src/ast/identifier_expression.h b/src/ast/identifier_expression.h
index 0f85346..b6b9b62 100644
--- a/src/ast/identifier_expression.h
+++ b/src/ast/identifier_expression.h
@@ -58,12 +58,6 @@
   /// @returns true if this identifier is for an intrinsic
   bool IsIntrinsic() const { return intrinsic_ != Intrinsic::kNone; }
 
-  /// Sets the identifier as a swizzle
-  void SetIsSwizzle() { is_swizzle_ = true; }
-
-  /// @returns true if this is a swizzle identifier
-  bool IsSwizzle() const { return is_swizzle_; }
-
   /// Clones this node and all transitive child nodes using the `CloneContext`
   /// `ctx`.
   /// @note Semantic information such as resolved expression type and intrinsic
@@ -84,9 +78,9 @@
   IdentifierExpression(const IdentifierExpression&) = delete;
 
   Symbol const sym_;
+
   Intrinsic intrinsic_ = Intrinsic::kNone;               // Semantic info
   std::unique_ptr<intrinsic::Signature> intrinsic_sig_;  // Semantic info
-  bool is_swizzle_ = false;                              // Semantic info
 };
 
 }  // namespace ast