[Diagnostics] Remove misplaced LoadExpr workaround for RawRepresentable

Since verifier is now in place to make sure that ParenExpr/ForceValueExpr
always preceed LoadExpr there is need to special case against incorrect
ordering in diagnostics.

Author: xedin

lib/Sema/CSDiag.cpp

@@ -4685,14 +4685,9 @@ static bool diagnoseRawRepresentableMismatch(CalleeCandidateInfo &CCI,
     return false;
 
   const Expr *expr = argExpr;
-  if (auto *tupleArgs = dyn_cast<TupleExpr>(argExpr)) {
+  if (auto *tupleArgs = dyn_cast<TupleExpr>(argExpr))
     expr = tupleArgs->getElement(bestMatchIndex);
-  } else if (auto *misplacedLoad = dyn_cast<LoadExpr>(argExpr)) {
-    // If there are multiple possible overloads for a single-argument call
-    // expression, the partially-typed-checked AST may have a load around the
-    // call parentheses instead of inside them.
-    expr = misplacedLoad->getSubExpr();
-  }
+
   expr = expr->getValueProvidingExpr();
 
   auto parameters = bestMatchCandidate->getParameters();