[wasm] Fix inconsistency in HasRunningCompileJob predicate.

This changes the predicate in question to only check for async compile
jobs belonging to a given Isolate, having an engine-wide predicate is
not desirable for draining message queues.

R=clemensh@chromium.org
BUG=v8:7424

Change-Id: If990378400cc4484d413c4d7771ec6deb6bfd244
Reviewed-on: https://chromium-review.googlesource.com/1158565
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54844}

src/d8.cc

@@ -3041,9 +3041,9 @@ void Shell::CompleteMessageLoop(Isolate* isolate) {
     DCHECK_GT(isolate_status_.count(isolate), 0);
     i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
     i::wasm::WasmEngine* wasm_engine = i_isolate->wasm_engine();
-    bool should_wait =
-        (options.wait_for_wasm && wasm_engine->HasRunningCompileJob()) ||
-        isolate_status_[isolate];
+    bool should_wait = (options.wait_for_wasm &&
+                        wasm_engine->HasRunningCompileJob(i_isolate)) ||
+                       isolate_status_[isolate];
     return should_wait ? platform::MessageLoopBehavior::kWaitForWork
                        : platform::MessageLoopBehavior::kDoNotWait;
   };

src/wasm/wasm-engine.cc

@@ -230,6 +230,14 @@ std::unique_ptr<AsyncCompileJob> WasmEngine::RemoveCompileJob(
   return result;
 }
 
+bool WasmEngine::HasRunningCompileJob(Isolate* isolate) {
+  base::LockGuard<base::Mutex> guard(&mutex_);
+  for (auto& entry : jobs_) {
+    if (entry.first->isolate() == isolate) return true;
+  }
+  return false;
+}
+
 void WasmEngine::AbortCompileJobsOnIsolate(Isolate* isolate) {
   // Iterate over a copy of {jobs_}, because {job->Abort} modifies {jobs_}.
   std::vector<AsyncCompileJob*> isolate_jobs;

src/wasm/wasm-engine.h

@@ -116,8 +116,9 @@ class V8_EXPORT_PRIVATE WasmEngine {
   // Remove {job} from the list of active compile jobs.
   std::unique_ptr<AsyncCompileJob> RemoveCompileJob(AsyncCompileJob* job);
 
-  // Returns true if at lease one AsyncCompileJob is currently running.
-  bool HasRunningCompileJob() const { return !jobs_.empty(); }
+  // Returns true if at least one AsyncCompileJob that belongs to the given
+  // Isolate is currently running.
+  bool HasRunningCompileJob(Isolate* isolate);
 
   // Cancel all AsyncCompileJobs that belong to the given Isolate. Their
   // deletion is delayed until all tasks accessing the AsyncCompileJob finish