[d8] Wait for wasm background compilation to complete

Prevent d8 from exiting while wasm background compilation is still
going on. This prevents the need to use the testRunner to execute
webassembly tests in d8.

R=yangguo@chromium.org
CC=ahaas@chromium.org

Change-Id: I86fb7ce260fc56ee87040742f77b0ff86b8fbd53
Reviewed-on: https://chromium-review.googlesource.com/964221Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51972}

src/d8.cc

@@ -40,6 +40,7 @@
 #include "src/trap-handler/trap-handler.h"
 #include "src/utils.h"
 #include "src/v8.h"
+#include "src/wasm/wasm-engine.h"
 
 #if !defined(_WIN32) && !defined(_WIN64)
 #include <unistd.h>  // NOLINT
@@ -3011,13 +3012,18 @@ bool ProcessMessages(Isolate* isolate,
 }  // anonymous namespace
 
 void Shell::CompleteMessageLoop(Isolate* isolate) {
-  ProcessMessages(isolate, [isolate]() {
+  auto get_waiting_behaviour = [isolate]() {
     base::LockGuard<base::Mutex> guard(isolate_status_lock_.Pointer());
     DCHECK_GT(isolate_status_.count(isolate), 0);
-    return isolate_status_[isolate]
-               ? platform::MessageLoopBehavior::kWaitForWork
-               : platform::MessageLoopBehavior::kDoNotWait;
-  });
+    i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+    i::wasm::CompilationManager* wasm_compilation_manager =
+        i_isolate->wasm_engine()->compilation_manager();
+    bool should_wait = wasm_compilation_manager->HasRunningCompileJob() ||
+                       isolate_status_[isolate];
+    return should_wait ? platform::MessageLoopBehavior::kWaitForWork
+                       : platform::MessageLoopBehavior::kDoNotWait;
+  };
+  ProcessMessages(isolate, get_waiting_behaviour);
 }
 
 bool Shell::EmptyMessageQueues(Isolate* isolate) {

src/wasm/compilation-manager.h

@@ -41,6 +41,9 @@ class CompilationManager {
   // AsyncCompileJob finish their execution.
   void AbortAllJobs();
 
+  // Returns true if at lease one AsyncCompileJob is currently running.
+  bool HasRunningCompileJob() const { return !jobs_.empty(); }
+
  private:
   AsyncCompileJob* CreateAsyncCompileJob(Isolate* isolate,
                                          std::unique_ptr<byte[]> bytes_copy,