ASTScope: Simplify a couple of getSourceRangeOfThisASTNode() methods

Author: slavapestov

include/swift/AST/ASTScope.h

@@ -797,7 +797,6 @@ class ParameterListScope final : public ASTScopeImpl {
 
 private:
   void expandAScopeThatDoesNotCreateANewInsertionPoint(ScopeCreator &);
-  SourceLoc fixupEndForBadInput(SourceRange) const;
 
 public:
   std::string getClassName() const override;

lib/AST/ASTScopeSourceRange.cpp

@@ -128,19 +128,14 @@ SourceRange AbstractStmtScope::getSourceRangeOfThisASTNode(
 
 SourceRange DefaultArgumentInitializerScope::getSourceRangeOfThisASTNode(
     const bool omitAssertions) const {
-  if (auto *dv = decl->getStructuralDefaultExpr())
-    return dv->getSourceRange();
-  return SourceRange();
+  return decl->getStructuralDefaultExpr()->getSourceRange();
 }
 
 SourceRange PatternEntryDeclScope::getSourceRangeOfThisASTNode(
     const bool omitAssertions) const {
   SourceRange range = getPatternEntry().getSourceRange();
-  if (endLoc.hasValue()) {
-    ASTScopeAssert(endLoc->isValid(),
-                   "BraceStmt ends before pattern binding entry?");
+  if (endLoc.hasValue())
     range.End = *endLoc;
-  }
   return range;
 }
 
@@ -244,20 +239,7 @@ SourceRange AbstractFunctionDeclScope::getSourceRangeOfThisASTNode(
 
 SourceRange ParameterListScope::getSourceRangeOfThisASTNode(
     const bool omitAssertions) const {
-  auto rangeForGoodInput = params->getSourceRange();
-  auto r = SourceRange(rangeForGoodInput.Start,
-                       fixupEndForBadInput(rangeForGoodInput));
-  ASTScopeAssert(getSourceManager().rangeContains(
-                     getParent().get()->getSourceRangeOfThisASTNode(true), r),
-                 "Parameters not within function?!");
-  return r;
-}
-
-SourceLoc ParameterListScope::fixupEndForBadInput(
-    const SourceRange rangeForGoodInput) const {
-  const auto s = rangeForGoodInput.Start;
-  const auto e = rangeForGoodInput.End;
-  return getSourceManager().isBeforeInBuffer(s, e) ? e : s;
+  return params->getSourceRange();
 }
 
 SourceRange ForEachPatternScope::getSourceRangeOfThisASTNode(