[wasm] Remove "WaitForTopTierFinished" method

The method is already misleading, as with dynamic tiering the "top tier"
is defined to be the same as the "baseline tier" (i.e. Liftoff). Hence
the method does not do what you would expect it to do.
Fixing it to wait for all functions to be compiled with TurboFan would
result in a deadlock, if we do not also trigger tier-up of all
functions.

Hence remove the method.

R=ahaas@chromium.org

Bug: v8:12899
Change-Id: I4ba76febd796f6a9ad1252e6d73a72e569fd648c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3657436
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80859}

src/wasm/compilation-environment.h

@@ -164,9 +164,6 @@ class V8_EXPORT_PRIVATE CompilationState {
       base::Vector<const int> lazy_functions,
       base::Vector<const int> liftoff_functions);
 
-  // Wait until top tier compilation finished, or compilation failed.
-  void WaitForTopTierFinished();
-
   // Set a higher priority for the compilation job.
   void SetHighPriority();
 

src/wasm/module-compiler.cc

@@ -858,11 +858,6 @@ void CompilationState::AddCallback(
   return Impl(this)->AddCallback(std::move(callback));
 }
 
-void CompilationState::WaitForTopTierFinished() {
-  Impl(this)->WaitForCompilationEvent(
-      CompilationEvent::kFinishedTopTierCompilation);
-}
-
 void CompilationState::SetHighPriority() { Impl(this)->SetHighPriority(); }
 
 void CompilationState::InitializeAfterDeserialization(