[NFC] Move DeclID from serialization/ASTBitCodes.h to AST/DeclID.h (#89873)

Previously, the DeclID is defined in serialization/ASTBitCodes.h under
clang::serialization namespace. However, actually the DeclID is not
purely used in serialization part. The DeclID is already widely used in
AST and all around the clang project via classes like `LazyPtrDecl` or
calling `ExternalASTSource::getExernalDecl()`. All such uses are via the
raw underlying type of `DeclID` as `uint32_t`. This is not pretty good.

This patch moves the DeclID class family to a new header `AST/DeclID.h`
so that the whole project can use the wrapped class `DeclID`,
`GlobalDeclID` and `LocalDeclID` instead of the raw underlying type.
This can improve the readability and the type safety.

1 files changed, 1 insertions, 2 deletions

diff --git a/clang/lib/Frontend/MultiplexConsumer.cpp b/clang/lib/Frontend/MultiplexConsumer.cpp
index 744ea70..9e885c8 100644
--- a/clang/lib/Frontend/MultiplexConsumer.cpp
+++ b/clang/lib/Frontend/MultiplexConsumer.cpp
@@ -52,8 +52,7 @@ void MultiplexASTDeserializationListener::TypeRead(
     Listeners[i]->TypeRead(Idx, T);
 }
 
-void MultiplexASTDeserializationListener::DeclRead(
-    serialization::DeclID ID, const Decl *D) {
+void MultiplexASTDeserializationListener::DeclRead(DeclID ID, const Decl *D) {
   for (size_t i = 0, e = Listeners.size(); i != e; ++i)
     Listeners[i]->DeclRead(ID, D);
 }