base: Add AsList() function to Value API.

chrome/test/perf/dom_checker_uitest.cc

Index: chrome/test/perf/dom_checker_uitest.cc
diff --git a/chrome/test/perf/dom_checker_uitest.cc b/chrome/test/perf/dom_checker_uitest.cc
index 6ca9c1a4681189215c4de2b0e4f820b69584326c..4196666ae1823491477c3a63cb109170453a61d0 100644
--- a/chrome/test/perf/dom_checker_uitest.cc
+++ b/chrome/test/perf/dom_checker_uitest.cc
@@ -175,12 +175,11 @@ class DomCheckerTest : public UITest {
     if (!value.get())
       return false;
 
-    EXPECT_TRUE(value->IsType(Value::TYPE_LIST));
-    if (!value->IsType(Value::TYPE_LIST))
+    EXPECT_TRUE(value->AsList());
+    ListValue* list_value = value->AsList();
+    if (!list_value)
       return false;
 
-    ListValue* list_value = static_cast<ListValue*>(value.get());
-
     // The parsed JSON object will be an array of strings, each of which is a
     // test failure. Add those strings to the results set.
     ListValue::const_iterator it = list_value->begin();