[api] Remove long-deprecated getters on WeakCallbackInfo

Bug: 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I986e3d3a54a07b5082a52e2bc7b5505e12589d98
Reviewed-on: https://chromium-review.googlesource.com/782324Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49557}

include/v8.h

@@ -433,20 +433,6 @@ class WeakCallbackInfo {
   V8_INLINE T* GetParameter() const { return parameter_; }
   V8_INLINE void* GetInternalField(int index) const;
 
-  V8_INLINE V8_DEPRECATED("use indexed version",
-                          void* GetInternalField1() const) {
-    return embedder_fields_[0];
-  }
-  V8_INLINE V8_DEPRECATED("use indexed version",
-                          void* GetInternalField2() const) {
-    return embedder_fields_[1];
-  }
-
-  V8_DEPRECATED("Not reliable once SetSecondPassCallback() was used.",
-                bool IsFirstPass() const) {
-    return callback_ != nullptr;
-  }
-
   // When first called, the embedder MUST Reset() the Global which triggered the
   // callback. The Global itself is unusable for anything else. No v8 other api
   // calls may be called in the first callback. Should additional work be