Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/ui/cocoa/view_id_util_browsertest.mm

Index: chrome/browser/ui/cocoa/view_id_util_browsertest.mm
diff --git a/chrome/browser/ui/cocoa/view_id_util_browsertest.mm b/chrome/browser/ui/cocoa/view_id_util_browsertest.mm
index 3fdcc0d92b72a77332dd20331b07fb4209907e58..95d3a6a85ee3f787d3e03684fdd305b27862b861 100644
--- a/chrome/browser/ui/cocoa/view_id_util_browsertest.mm
+++ b/chrome/browser/ui/cocoa/view_id_util_browsertest.mm
@@ -62,7 +62,8 @@ class ViewIDTest : public InProcessBrowserTest {
         test::WaitForBookmarkModelToLoad(bookmark_model);
 
       bookmark_utils::AddIfNotBookmarked(
-          bookmark_model, GURL(content::kAboutBlankURL), ASCIIToUTF16("about"));
+          bookmark_model, GURL(content::kAboutBlankURL),
+          base::ASCIIToUTF16("about"));
     }
 
     for (int i = VIEW_ID_TOOLBAR; i < VIEW_ID_PREDEFINED_COUNT; ++i) {