Reland: [Compiler] Enable handles created during parsing and scope analysis to be deferred.

src/compilation-info.h

Index: src/compilation-info.h
diff --git a/src/compilation-info.h b/src/compilation-info.h
index 46fb3cb9ace02be2c32141fa3175955b5b5aa857..2ec77ab09ec78c01244b966c014f979f673c97fa 100644
--- a/src/compilation-info.h
+++ b/src/compilation-info.h
@@ -232,9 +232,10 @@ class V8_EXPORT_PRIVATE CompilationInfo final {
   // Determines whether or not to insert a self-optimization header.
   bool ShouldSelfOptimize();
 
-  void set_deferred_handles(DeferredHandles* deferred_handles) {
-    DCHECK(deferred_handles_ == NULL);
-    deferred_handles_ = deferred_handles;
+  void set_deferred_handles(std::shared_ptr<DeferredHandles> deferred_handles);
+  void set_deferred_handles(DeferredHandles* deferred_handles);
+  std::shared_ptr<DeferredHandles> deferred_handles() {
+    return deferred_handles_;
   }
 
   void ReopenHandlesInNewHandleScope();
@@ -364,7 +365,7 @@ class V8_EXPORT_PRIVATE CompilationInfo final {
   // CompilationInfo allocates.
   Zone* zone_;
 
-  DeferredHandles* deferred_handles_;
+  std::shared_ptr<DeferredHandles> deferred_handles_;
 
   // Dependencies for this compilation, e.g. stable maps.
   CompilationDependencies dependencies_;