If a CXXRecordDecl is a class template, the 'this' type should be the injected class name type. Fixes pr4383.

llvm-svn: 73284
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 94daf48..8430da2 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -260,7 +260,12 @@
   // the type of this is const volatile X*.
 
   assert(isInstance() && "No 'this' for static methods!");
-  QualType ClassTy = C.getTagDeclType(const_cast<CXXRecordDecl*>(getParent()));
+
+  QualType ClassTy;
+  if (ClassTemplateDecl *TD = getParent()->getDescribedClassTemplate())
+    ClassTy = TD->getInjectedClassNameType(C);
+  else
+    ClassTy = C.getTagDeclType(const_cast<CXXRecordDecl*>(getParent()));
   ClassTy = ClassTy.getWithAdditionalQualifiers(getTypeQualifiers());
   return C.getPointerType(ClassTy).withConst();
 }