Fix crash on undeclared identifier inside a vector (#3653)

Fixes #3357

tools/clang/lib/Sema/TreeTransform.h

@@ -2022,8 +2022,11 @@ public:
     ExprResult result;
     DeclarationName Name(&Accessor);
 
-    return hlsl::LookupVectorMemberExprForHLSL(&getSema(), *Base, Name, IsArrowFalse, OpLoc, AccessorLoc);
-
+    ExprResult ER = hlsl::MaybeConvertMemberAccess(&getSema(), Base);
+    if (ER.isInvalid()) {
+      return ExprError();
+    }
+    return hlsl::LookupVectorMemberExprForHLSL(&getSema(), *ER.get(), Name, IsArrowFalse, OpLoc, AccessorLoc);
   }
 
   // HLSL Changes End

tools/clang/test/HLSLFileCheck/hlsl/operators/swizzle/swizzleInCorrectDelayedTyposInExpr.hlsl

@@ -5,6 +5,7 @@
 // It requires a number of conditions to get there.
 
 // CHECK: error: use of undeclared identifier 'some_var_2'; did you mean 'some_var_1'
+// CHECK: error: use of undeclared identifier 'some_var_3'
 
 float3 some_fn(float4 a, float b) { return b; }
 float4 foo(int i) { return i; }
@@ -17,7 +18,7 @@ float3 repro() {
   // to resolve the vector member expression
   // using hlsl::LookupVectorMemberExprForHLSL
   float4 some_var_1;
-  return some_fn(some_var_2, foo(0).xyz);
+  return some_fn(some_var_2, foo(0).xyz) + some_other_fn(1.0.xxxx, 0.0.xxxx, some_var_3);
 }
 float3 main(float4 input : IN) : OUT {
   return repro();