Use mayNotBeMainThread() for wrapper optimization

third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp

Index: third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp
diff --git a/third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp b/third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp
index 93c9e3b3b4ce83c460d0ee7a2d0bbf914f48f061..ea3e309fee1acdb8709d9cb74e9c6888a5a371a4 100644
--- a/third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp
+++ b/third_party/WebKit/Source/core/editing/VisibleUnitsTest.cpp
@@ -4,13 +4,14 @@
 
 #include "core/editing/VisibleUnits.h"
 
+#include <ostream>  // NOLINT
+#include "bindings/core/v8/V8BindingForTesting.h"
 #include "core/dom/Text.h"
 #include "core/editing/EditingTestBase.h"
 #include "core/editing/VisiblePosition.h"
 #include "core/html/TextControlElement.h"
 #include "core/layout/LayoutTextFragment.h"
 #include "core/layout/line/InlineTextBox.h"
-#include <ostream>  // NOLINT
 
 namespace blink {
 
@@ -107,6 +108,8 @@ TEST_F(VisibleUnitsTest, associatedLayoutObjectOfFirstLetterPunctuations) {
 }
 
 TEST_F(VisibleUnitsTest, associatedLayoutObjectOfFirstLetterSplit) {
+  V8TestingScope scope;
+
   const char* bodyContent =
       "<style>p:first-letter {color:red;}</style><p id=sample>abc</p>";
   setBodyContent(bodyContent);
@@ -1365,6 +1368,8 @@ TEST_F(VisibleUnitsTest, mostBackwardCaretPositionFirstLetter) {
 }
 
 TEST_F(VisibleUnitsTest, mostBackwardCaretPositionFirstLetterSplit) {
+  V8TestingScope scope;
+
   const char* bodyContent =
       "<style>p:first-letter {color:red;}</style><p id=sample>abc</p>";
   setBodyContent(bodyContent);