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

chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm

Index: chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm
diff --git a/chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm b/chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm
index 6dfea685e37deadcc64162d6b4593139abb74e52..0bfcd6f33dc57ce514ad48b3a2553aad80c57e06 100644
--- a/chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm
+++ b/chrome/browser/ui/cocoa/notifications/balloon_controller_unittest.mm
@@ -79,7 +79,7 @@ class BalloonControllerTest : public ChromeRenderViewHostTestHarness {
 
 TEST_F(BalloonControllerTest, ShowAndCloseTest) {
   Notification n(GURL("http://www.google.com"), GURL("http://www.google.com"),
-      ASCIIToUTF16("http://www.google.com"), base::string16(),
+      base::ASCIIToUTF16("http://www.google.com"), base::string16(),
       new NotificationObjectProxy(-1, -1, -1, false));
   scoped_ptr<Balloon> balloon(
       new Balloon(n, profile(), collection_.get()));
@@ -95,7 +95,7 @@ TEST_F(BalloonControllerTest, ShowAndCloseTest) {
 
 TEST_F(BalloonControllerTest, SizesTest) {
   Notification n(GURL("http://www.google.com"), GURL("http://www.google.com"),
-      ASCIIToUTF16("http://www.google.com"), base::string16(),
+      base::ASCIIToUTF16("http://www.google.com"), base::string16(),
       new NotificationObjectProxy(-1, -1, -1, false));
   scoped_ptr<Balloon> balloon(
       new Balloon(n, profile(), collection_.get()));