Use ScopedTaskEnvironment instead of MessageLoop in tests that use v8.

content/test/blink_test_environment.cc

Index: content/test/blink_test_environment.cc
diff --git a/content/test/blink_test_environment.cc b/content/test/blink_test_environment.cc
index 2b9a55c35ab30766e0069268225d88e961c189ea..4dfab3eab9e013f3626ff84314b10ebbb86fc09e 100644
--- a/content/test/blink_test_environment.cc
+++ b/content/test/blink_test_environment.cc
@@ -7,9 +7,9 @@
 #include <string>
 
 #include "base/command_line.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/string_tokenizer.h"
+#include "base/test/scoped_task_environment.h"
 #include "base/test/test_discardable_memory_allocator.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
 #include "build/build_config.h"
@@ -36,17 +36,16 @@ namespace {
 
 class TestEnvironment {
  public:
-#if defined(OS_ANDROID)
-  // Android UI message loop goes through Java, so don't use it in tests.
-  typedef base::MessageLoop MessageLoopType;
-#else
-  typedef base::MessageLoopForUI MessageLoopType;
+  TestEnvironment()
+#if !defined(OS_ANDROID)
+      // On Android, do not pump UI messages on the main thread because that
+      // would go through Java.

[gab, 2017/05/03 17:38:36]

// On Android, Java pumps UI messages.

[fdoray, 2017/05/03 20:48:44]

Done.

+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI)
 #endif
-
-  TestEnvironment() {
-    main_message_loop_.reset(new MessageLoopType);
-
-    // TestBlinkWebUnitTestSupport must be instantiated after MessageLoopType.
+  {
+    // TestBlinkWebUnitTestSupport must be instantiated after
+    // ScopedTaskEnvironment.

[gab, 2017/05/03 17:38:36]

Move this comment to the member and make both of them regular members (no reason
for them to be std::unique_ptr anymore IMO)...

[fdoray, 2017/05/03 20:48:44]

Done.

     blink_test_support_.reset(new TestBlinkWebUnitTestSupport);
     content_initializer_.reset(new content::TestContentClientInitializer());
 
@@ -62,7 +61,8 @@ class TestEnvironment {
   }
 
  private:
-  std::unique_ptr<MessageLoopType> main_message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
+
   std::unique_ptr<TestBlinkWebUnitTestSupport> blink_test_support_;
   std::unique_ptr<TestContentClientInitializer> content_initializer_;
   base::TestDiscardableMemoryAllocator discardable_memory_allocator_;