Remove unused ScopedPersistent constructor overload from v8::MaybeLocal

Bug: 1013149
Change-Id: Ifea542795b864dcd01a2f2e72f112748e3ec35e2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2619420
Auto-Submit: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#842019}

third_party/blink/renderer/platform/bindings/scoped_persistent.h

@@ -51,12 +51,6 @@ class ScopedPersistent {
   ScopedPersistent(v8::Isolate* isolate, v8::Local<T> handle)
       : handle_(isolate, handle) {}
 
-  ScopedPersistent(v8::Isolate* isolate, v8::MaybeLocal<T> maybe) {
-    v8::Local<T> local;
-    if (maybe.ToLocal(&local))
-      handle_.Reset(isolate, local);
-  }
-
   ~ScopedPersistent() { Clear(); }
 
   ALWAYS_INLINE v8::Local<T> NewLocal(v8::Isolate* isolate) const {