[global-handles] Deprecate unused methods

Bug: chromium:923361
Change-Id: I520b2778b8a2fe3fcd52570f3a91758bc949f374
Reviewed-on: https://chromium-review.googlesource.com/c/1425897
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58975}

include/v8.h

@@ -568,7 +568,9 @@ template <class T> class PersistentBase {
                     V8_INLINE bool IsIndependent() const);
 
   /** Checks if the handle holds the only reference to an object. */
-  V8_INLINE bool IsNearDeath() const;
+  V8_DEPRECATE_SOON(
+      "Garbage collection internal state should not be relied on.",
+      V8_INLINE bool IsNearDeath() const);
 
   /** Returns true if the handle's reference is weak.  */
   V8_INLINE bool IsWeak() const;
@@ -8317,7 +8319,9 @@ class V8_EXPORT Isolate {
    * garbage collection but is free to visit an arbitrary superset of these
    * objects.
    */
-  void VisitHandlesForPartialDependence(PersistentHandleVisitor* visitor);
+  V8_DEPRECATE_SOON(
+      "Use VisitHandlesWithClassIds",
+      void VisitHandlesForPartialDependence(PersistentHandleVisitor* visitor));
 
   /**
    * Iterates through all the persistent handles in the current isolate's heap

test/cctest/test-api.cc

@@ -21164,7 +21164,17 @@ TEST(PersistentHandleInNewSpaceVisitor) {
   CHECK_EQ(42, object2.WrapperClassId());
 
   Visitor42 visitor(&object2);
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated"
+#endif
+  // VisitHandlesForPartialDependence is marked deprecated. This test will be
+  // removed with the API method.
   isolate->VisitHandlesForPartialDependence(&visitor);
+#if __clang__
+#pragma clang diagnostic pop
+#endif
+
   CHECK_EQ(1, visitor.counter_);
 
   object1.Reset();