Use GetEnteredOrMicrotaskContext instead of GetEnteredContext

This CL replaces all usage of v8::Isolate::GetEnteredContext in Blink
with GetEnteredOrMicrotaskContext.
GetEnteredOrMicrotaskContext should be the better fit here as the
EnteredContext may be unrelated to the currently running script's context
when it's in the microtask queue.

chromium: 887920
Change-Id: I9da9777fb3b365fa181d2d9660c36a071734acf3
Reviewed-on: https://chromium-review.googlesource.com/c/1319220Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605964}

third_party/blink/renderer/bindings/core/v8/custom/v8_dev_tools_host_custom.cc

@@ -155,7 +155,7 @@ void V8DevToolsHost::showContextMenuAtPointMethodCustom(
   } else {
     v8::Local<v8::Object> window_wrapper =
         V8Window::findInstanceInPrototypeChain(
-            isolate->GetEnteredContext()->Global(), isolate);
+            isolate->GetEnteredOrMicrotaskContext()->Global(), isolate);
     if (window_wrapper.IsEmpty())
       return;
     DOMWindow* window = V8Window::ToImpl(window_wrapper);

third_party/blink/renderer/bindings/core/v8/v8_initializer.cc

@@ -242,7 +242,7 @@ void V8Initializer::MessageHandlerInMainThread(v8::Local<v8::Message> message,
   DCHECK(IsMainThread());
   v8::Isolate* isolate = v8::Isolate::GetCurrent();
 
-  if (isolate->GetEnteredContext().IsEmpty())
+  if (isolate->GetEnteredOrMicrotaskContext().IsEmpty())
     return;
 
   // If called during context initialization, there will be no entered context.