Update tests to not use to-be-removed V8 handle operations.

chrome/test/base/v8_unit_test.h

Index: chrome/test/base/v8_unit_test.h
diff --git a/chrome/test/base/v8_unit_test.h b/chrome/test/base/v8_unit_test.h
index 69f4af1ac8bd7a1fb8b96dd9d6180f82fc58cc35..d03ba4cd351753aa8e7a5d388b18a5752a0d1db6 100644
--- a/chrome/test/base/v8_unit_test.h
+++ b/chrome/test/base/v8_unit_test.h
@@ -74,11 +74,13 @@ class V8UnitTest : public testing::Test {
   // Initializes paths and libraries.
   void InitPathsAndLibraries();
 
+  v8::Isolate* isolate_;
+
   // Handle scope that is used throughout the life of this class.
   v8::HandleScope handle_scope_;
 
   // Context for the JavaScript in the test.
-  v8::Handle<v8::Context> context_;
+  v8::Persistent<v8::Context> context_;
 
   // User added libraries.
   std::vector<base::FilePath> user_libraries_;