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

chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm

Index: chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm
diff --git a/chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm b/chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm
index 37f8034a1c9847224d66d8e82a1b87d2bf80e0cd..9e583798ff96684942bd03ec675bc1d9abd385f9 100644
--- a/chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm
+++ b/chrome/browser/ui/cocoa/confirm_bubble_controller_unittest.mm
@@ -58,11 +58,11 @@ TestConfirmBubbleModel::~TestConfirmBubbleModel() {
 }
 
 base::string16 TestConfirmBubbleModel::GetTitle() const {
-  return ASCIIToUTF16("Test");
+  return base::ASCIIToUTF16("Test");
 }
 
 base::string16 TestConfirmBubbleModel::GetMessageText() const {
-  return ASCIIToUTF16("Test Message");
+  return base::ASCIIToUTF16("Test Message");
 }
 
 gfx::Image* TestConfirmBubbleModel::GetIcon() const {
@@ -76,7 +76,8 @@ int TestConfirmBubbleModel::GetButtons() const {
 
 base::string16 TestConfirmBubbleModel::GetButtonLabel(
     BubbleButton button) const {
-  return button == BUTTON_OK ? ASCIIToUTF16("OK") : ASCIIToUTF16("Cancel");
+  return button == BUTTON_OK ? base::ASCIIToUTF16("OK")
+                             : base::ASCIIToUTF16("Cancel");
 }
 
 void TestConfirmBubbleModel::Accept() {
@@ -88,7 +89,7 @@ void TestConfirmBubbleModel::Cancel() {
 }
 
 base::string16 TestConfirmBubbleModel::GetLinkText() const {
-  return ASCIIToUTF16("Link");
+  return base::ASCIIToUTF16("Link");
 }
 
 void TestConfirmBubbleModel::LinkClicked() {