[IDE] Pass a SourceRange instead of a CharSourceRange in SemaAnnotator::passReference

Most `SemaAnnotator`s don’t actually care about the char source range. Instead, they only care about the start location of the reference, which is also included in `SourceRange`. Computing a `CharSourceRange` from a `SourceRange` is kind of expensive because it needs to start a new lexer.

To avoid this overhead, pass `SourceRange` to `SemaAnnotator::passReference` and related functions and let the clients compute the `CharSourceRange` when needed.

This reduces the overhead of index-while-building by about 10%.

lib/Refactoring/ExtractExprBase.cpp

@@ -26,8 +26,8 @@ struct ReferenceCollector : public SourceEntityWalker {
   SmallVector<ValueDecl *, 4> References;
 
   ReferenceCollector(Expr *E) { walk(E); }
-  bool visitDeclReference(ValueDecl *D, CharSourceRange Range,
-                          TypeDecl *CtorTyRef, ExtensionDecl *ExtTyRef, Type T,
+  bool visitDeclReference(ValueDecl *D, SourceRange Range, TypeDecl *CtorTyRef,
+                          ExtensionDecl *ExtTyRef, Type T,
                           ReferenceMetaData Data) override {
     References.emplace_back(D);
     return true;